• Journal of the Korean Crystal Growth and Crystal Technology
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• v.17 no.5
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• pp.179-186
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• 2007

Single crystal $CdGa_2Se_4$ layers were grown on a thoroughly etched semi-insulating GaAs(100) substrate at $420^{\circ}C$ with the hot wall epitaxy(HWE) system by evaporating the polycrystal source of $CdGa_2Se_4$ at $630^{\circ}C$. The crystalline structure of the single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction(DCXD). The carrier density and mobility of single crystal $CdGa_2Se_4$ thin films measured with Hall effect by van der Pauw method are $8.27{\times}10^{17}cm^{-3},\;345cm^2/V{\cdot}s$ at 293 K, respectively. The photocurrent and the absorption spectra of $CdGa_2Se_4/SI$(Semi-Insulated) GaAs(100) are measured ranging from 293 K to 10 K. The temperature dependence of the energy band gap of the $CdGa_2Se_4$ obtained from the absorption spectra was well described by the Varshni's relation $E_g(T)=2.6400eV-(7.721{\times}10^{-4}eV/K)T^2/(T+399K)$. Using the photocurrent spectra and the Hopfield quasicubic model, the crystal field energy(${\Delta}cr$) and the spin-orbit splitting energy(${\Delta}so$) far the valence band of the $CdGa_2Se_4$ have been estimated to be 106.5 meV and 418.9 meV at 10 K, respectively. The three photocurrent peaks observed at 10 K are ascribed to the $A_{1^-},\;B_{1^-},\;and\;C_{11}-exciton$ peaks.

• Proceedings of the KIEE Conference
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• 2006.07c
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• pp.1341-1342
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• 2006

Electrical characteristics of field-effect thin film transistors (TFTs) with p-channels of CdTe/CdHgTe core-shell nanocrystals are investigated in this paper. For the fabrication of bottom- and top-gate TFTs, CdTe/CrHgTe nanocrystals synthesized by colloidal method are first dispersed on oxidized p+ Si substrates by spin-coating, the dispersed nanoparticles are sintered at $150^{\circ}C$ to form the channels for the TFTs, and $Al_{2}O_{3}$ layers are deposited on the channels. A representative bottom-gate field-effect TFT with a bottom-gate $SiO_2$ layer exhibits a mobility of $0.21cm^2$/ Vs and an Ion/Ioff ratio of $1.5{\times}10^2$ and a representative top-gate field-effect TFT with a top-gate $Al_{2}O_{3}$ layer provides a field-effect mobility of $0.026cm^2$/ Vs and an Ion/Ioff ratio of $2.5{\times}10^2$. $Al_{2}O_{3}$ was deposited for passivation of CdTe/CdHgTe core-shell nanocrystal layer, resulting in enhanced hole mobility, Ior/Ioff ratio by 0.25, $3{\times}10^3$, respectively. The CdTe/CdHgTe nanocrystal-based TFTs with bottom- and top gate geometries are compared in this paper.

• Journal of Dairy Science and Biotechnology
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• v.14 no.2
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• pp.229-245
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• 1996

1. CM-Sephadex C-50-120 column을 사용하여 HLF를 효과적으로 정제하였다. CM-Sepha-dex 50-120 column chromatography를 수행한 결과, HLF는 NaCl 350 mM-500 mM 사이에서 용출되었으며, 용출된 분획을 SDS-PAGE를 수행해서 단일 band를 확인하였다. Anti-HLF antibody를 이용한 Western blotting 결과 nitrocellulose paper 상에 단일 band 가 나타나므로 HLF 가 효과적으로 정제되었다는 것을 알 수 있었다. 2. Con A, PWM, PWA LPS 등의 자극원으로 단핵구와 대식세포를 자극한 다음 BLF를처리한 배 양액을 IL-1 bioassy한 결과는 Con A 33%, PMA 33%, PWM 15%, LPS 35% 이고, HLF로 처리하여 IL-1 bioassay를 한 결과는 Con A 15%, PMA 22%, PWM 10%, LPS 5%로 감소된 것으로 나타났다. 3. K-562 세포를 이용한 colony forming assay에서 BLF가 10 g/ml일 때는 30%, 30 g/ml일 때는 35%, HLF는 10 g/ml일 때는 5%,30 g/ml일 때는 30%의 저해를 나타냈다. 4. Lactoferrin의 면역증강효과를 알아보기 위하여 hapten인 VCR-BSA를 투여 한 후, 생성되는 항체생성능력을 ELISA로 비교하였다. 그 결과 HLF 및 BLF 투여군에서 대조군에 비하여 adjuvant 효과를 관찰할 수 있었다. 또한 이때 macrophage 수는 대조군에 비하여 HLF와 BLF를 투여한 군이 증가됨을 알 수 있었다. 이러한 결과로 미루어 볼 때 LF는 macrophage를 활성화 시켜서 항체 생성 능력을 증가시키는 효과가 있음을 관찰할 수 있었다. 5. Balb/c mouse의 thymus로부터 분리한 CD4- CD8- 세포를 BLF로 처리하여 24 시간 배양한 후 CB4$^-$ CD8$^-$ 세포의 분화를 측정한 결과, CD4$^-$를 CD4$^+$ 로 분화하였다. 그리고 HLF로 처리하여 24 시간 배양 후 CD4$^-$ CD8$^-$ 세포의 분화를 측정한 결과, CD4$^-$ CD8$^-$를 CD4$^+$ CD8$^+$ 로 분화하였다. 6. Lactoferrin이 T cell의 IL-2 production에 미치는 영향은 PMA 처리군, PMA+OKT3처리군, LF 단독 처리군 보다 PMA+OKT3+LF를 처리한 군이 IL-2 생성에 영향을 미쳤다. 7. Lfcin B의 단일크론항체에 의해 인식되어지는 Lfcin B의 항원결정기는 ‘QWR’로 밝혀졌다.

• Bulletin of the Korean Chemical Society
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• v.19 no.11
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• pp.1222-1227
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• 1998

The crystal structure of a benzene sorption complex of fully dehydrated Cd2+-exchanged zeolite X, Cd46Si100Al92O384·43C6H6 (a=24.880(6) Å), has been determined by single-crystal X-ray diffraction techniques in the cubic space group Fd3 at 21 ℃. The crystal was prepared by ion exchange in a flowing stream of 0.05 M aqueous Cd(NO3)2 for 3 d, followed by dehydration at 400 ℃ and 2 x 10-6 Torr for 2 d, followed by exposure to about 92 Torr of benzene vapor at 22 ℃. The structure was determined in this atmosphere and refined to the final error indices R1=0.054 and Rw=0.066 with 561 reflections for which I > 3σ(I). In this structure, Cd2+ ions are found at four crystallographic sites: eleven Cd2+ ions are at site 1, at the centers of the double six-oxygen rings; six Cd2+ ions lie at site I', in the sodalite cavity opposite to the double six-oxygen rings; and the remaining 29 Cd2+ ions are found at two nonequivalent threefold axes of unit cell, sites Ⅱ' (in the sodalite cavity ) and site Ⅱ (in the supercage) with occupancies of 2 and 27 ions, respectively. Each of these Cd2+ ions coordinates to three framework oxylkens, either at 2.173(13) or 2.224(10) Å, respectively, and extends 0.37 Å into the sodalite unit or 0.60 Å into the supercage from the plane of the three oxygens to which it is bound. The benzene molecules are found at two distinct sites within the supercages. Twenty-seven benzenes lie on threefold axes in the large cavities where they interact facially with the latter 27 site-Ⅱ Cd2+ ions (Cd2+-benzene center=2.72 Å; occupancy=27 molecules/32 sites). The remaining sixteen benzene molecules are found in 12ring planes; occupancy=16 molecules/16 sites. Each hydrogen of these sixteen benzenes is ca. 2.8/3.0 Å from three 12-ring oxygens where each is stabilized by multiple weak electrostatic and van der Waals interactions with framework oxygens.

• The Journal of Korean Obstetrics and Gynecology
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• v.35 no.3
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• pp.24-36
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• 2022

Objectives: Excessive melanin production leads to skin pigmentation, which causes various cosmetic and health problems. Citrus unshiu Markovich peel (CS) and Cimicifuga dahurica (CD) have long been widely used as a oriental medicinal plant because of their pharmacological properties including anti-ulcer, anti-oxidant, and anti-inflammatory properties. Methods: In this study, we investigated the inhibitory effects of CS, CD extracts or CS:CD=1:2 mixture on melanogenesis according to the various extraction methods. CS and CD extracted were prepared by ethanol extraction (EE), ultrasonification extraction (USE), Supercritical extraction (SCE), reflux extraction (RE), respectively. Results: DPPH radical scavenging and tyrosinase inhibitory activity of CD extracts or CS:CD=1:2 mixture were increased in dose-dependent manners. In addition, we evaluated the effect of CS, CD extracts or CS:CD=1:2 mixture on tyrosinase activity and melanogenesis in α-melanocyte stimulating hormone-induced B16-F10 melanoma cells. CS, CD extracts or CS:CD=1:2 mixture significantly inhibited tyrosinase activity and melanogenesis at 10-200 ㎍/mL. Conclusions: Therefore, our study suggests that CS and CD extracts have potential as a safe treatment for excessive pigmentation or as a natural ingredient in cosmetics.

• Journal of Nutrition and Health
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• v.30 no.3
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• pp.252-265
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• 1997

This study was performed to investigate effect of dietary fibers in rice and barley on glucose, lipid and cadmium (Cd) metabolism in the rat. Fifty-six male Spague-Dawley rats weighing 244.6$\pm$2.7g were blocked into eight groups according to body weight and raised for four weeks with diets containing 0 or 0.04%(w/w) CdCl2 and four different carbohydrate sources, starch, rice flour, barley flour and mixture of rice and barley flour(7 : 3, w/w). Total dietary fibers and $\beta$-glucan contents of barley were about three times higher than those of rice (10.75% vs. 3.94%, 3.11% vs. 1.06%, respectively). Food intake, weight gain, food efficiency ratio, liver and kidney weights were lower in Cd exposed groups, and barley group among Cd exposed animals showed highest weight gain, food efficiency ratio and organ weights. Fasting serum glucose levels were not significantly different among groups, Serum cholesterol level was lowest in Cd exposed barley group. Serum HDL-cholesterol level was higher in none-Cd exposed starch and barley groups, and HDL-cholesterol : total cholesterol ratios were higher in none-Cd rice and mixed flour groups than other groups. Liver total lipid and triglyceride levels were lowest in barley groups regardless of Cd administration. Fecal total lipid, cholesterol and triglyceride excretions were high in barley and mixed flour groups. Liver Cd concentrations were low in Cd exposed barley and mixed flour groups. In Cd exposed barley group, fecal weight and Cd excretion were highest and Cd retention ratio was lowest among groups. Small intestine metallothionein(MT) concentration was highest in Cd exposed rice group, and kidney MT concentration was highest in Cd exposed barley group. In conclusion, cereals showed different effects on lipid and Cd metabolism that might be mediated by dietary fibers in cereals. Especially $\beta$-glucan-rich barley group showed greatest lipid and Cd lowering effects by increasing fecal lipids and Cd excretions.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.1721-1724
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• 2013

Objective: To investigate the effect of epirubicin on soluble CD25 (sCD25) secretion by CD4+CD25+ regulatory T (Treg) cells isolated from diffuse large B-cell lymphoma (DLBCL) patients. Methods: Treg cells were isolated from the peripheral blood mononuclear cells isolated from the newly diagnosed DBLCL patients. The concentration of sCD25 in the supernatant was determined with a commercial sCD25 (IL-2R) enzyme-linked immunosorbent assay (ELISA) kit. The fluorescence intensity of CD25 was detected by flow cytometry. Results: Cell survival rate was significantly decreased along with the increase of epirubicin concentration after treatment for 24 h. There was also a significant difference in the concentration of sCD25 between the epirubicin group and the control group (P<0.01). A positive correlation between the Treg cells survival rate and the concentration of sCD25 was detected (r=0.993, P<0.01). When equal numbers of CD4+CD25+ Treg cells of the epirubicin group and the control group were cultured for another 24 h without epirubicin the CD25 fluorescence intensity on the surface of Treg cells was obviously higher in the epirubicin group than that in the control group (P<0.01), while the sCD25 concentration in the supernatant in the epirubicin group was significantly lower than that in the control group (P<0.05). Conclusion: Epirubicin may improve the body's immune functions by inhibiting the sCD25 secretion by Treg cells in DLBCL patients.

• Bulletin of the Korean Chemical Society
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• v.34 no.3
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• pp.856-862
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• 2013

The photoanode electrode of $TiO_2$ nanotubes (NTs) anchored with ZnS/CdSSe/CdS quantum dots (QDs) was prepared by anodization of Ti metal and successive ionic layer adsorption and reaction (SILAR) procedure. The tuning of the band gap of CdSSe was done with controlled composition of Cd, S, or Se during the SILAR. A ladder-like energy structure suitable for carrier transfer was attained with the photoanode electrode. The power conversion efficiency (PCE) of our solar cell fabricated with the regular array of $TiO_2$ NTs anchored with CdSSe/CdS or CdSe/CdS QDs [i.e., (CdSSe/CdS/$TiO_2NTs$) or (CdSe/CdS/$TiO_2NTs$)] was PCE = 3.49% and 2.81% under the illumination at 100 mW/$cm^2$, respectively. To protect the photocorrosion of our solar cell from the electrolyte and to suppress carrier recombination, ZnS was introduced onto CdSSe/CdS. The PCE of our solar cell with the structure of a photoanode electrode, (ZnS/CdSSe/CdS/$TiO_2$ NTs/Ti) was 4.67% under illumination at 100 mW/$cm^2$.

• Korean Journal of Materials Research
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• v.30 no.1
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• pp.1-7
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• 2020

Doping or incorporation with exotic elements are two manners to regulate the optoelectronic properties of transparent conducting (TCO) cadmium oxide (CdO). Nevertheless, the method of doping host CdO by CdTe semiconductor is of high importance. The structural, optical, and electrical properties of CdTe-doped CdO films are studied for the sake of promoting their conducting parameters (CPs), including their conductivity, carrier concentration, and carrier mobility, along with transparency in the NIR spectral region; these are then compared with the influence of doping the host CdO by pure Te ions. X-ray fluorescence (XRF), X-ray diffraction (XRD), optical absorption spectroscopy, and electrical measurements are used to characterise the deposited films prepared by thermal evaporation. Numerous results are presented and discussed in this work; among these results, the optical properties are studied through a merging of concurrent BGN (redshift) and BGW (blue shift) effects as a consequence of doping processes. The impact of hydrogenation on the characterisations of the prepared films is investigated; it has no qualitative effect on the crystalline structure. However, it is found that TCO-CPs are improved by the process of CdTe doping followed by hydrogenation. The utmost TCO-CP improvements are found with host CdO film including ~ 1 %Te, in which the resistivity decreases by ~ 750 %, carrier concentration increases by 355 %, and mobility increases by ~ 90 % due to the increase of N_carr. The improvement of TCO-CPs by hydrogenation is attributed to the creation of O-vacancies because of H₂ molecule dissociation in the presence of Te ions. These results reflect the potential of using semiconductor CdTe -doped CdO thin films in TCO applications. Nevertheless, improvements of the host CdO CPs with CdTe dopant are of a lesser degree compared with the case of doping the host CdO with pure Te ions.

• The Journal of Pediatrics of Korean Medicine
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• v.21 no.1
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• pp.227-252
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• 2007

Objectives : In order to investigate the effect of Bobitang on SD rats with deteriorated immunity caused by methotrexate. Methods : The test sample were dosed once a day for 14 days by gastric gavage at a dosage 1,000, 500 and $250mg/kg/10m{\ell}$ from 2 days after last MTX-dosing, and the changes on body weight and gains, spleen weight and total blood leukocyte numbers, total lymphocyte numbers, the percentage of B-cell, T-cell, CD3+CD4+ T-cell, CD3+CD8+ T-cell and CD4+/CD8+ T-cell ratios in the blood and spleen were observed. Results : The changes on body weight gains, the spleen weight, the total blood leukocyte numbers, the total lymphocyte numbers in the blood and spleen, the ratio of T-cell in the blood and spleen, the ratio of CD3+CD4+ T-cell in the blood and spleen were increased significantly in BBT Extracts groups as compared with control group. The ratio of B-cell in the blood and spleen was not increased significantly in BBT Extracts groups as compared with control group. The percentage of CD3+CD8+ T-cell in the blood and spleen was decreased significantly in BBT Extracts groups as compared with control group. The ratio of CD4+/CD8+ T-cell in blood and spleen was increased significantly in BBT Extracts group as compared with control group. Conclusions : According to the above results, Bobi-Tang has an effect of increasing immune responses on SD rats with deteriorated immunity caused by methotrexate.