• Bulletin of the Korean Chemical Society
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• 제35권1호
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• pp.123-128
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• 2014

In this study, we have investigated the flow rate effects of Ag nanoparticle (NP) suspensions on the progress of the cell cycle by using a microfluidic image cytometry (${\mu}FIC$)-based approach. Compared with the conventional "static" exposure conditions, enhancements in G2 phase arrest were observed for the cells under continuously flowing "dynamic" exposure conditions. The "dynamic" exposure conditions, which mimic in vivo systems, induced an enhanced cytotoxicity by accelerating G2 phase arrest and subsequent apoptosis processes. Moreover, we have also shown that the increases in delivered NP dose due to the continuous supply of Ag NPs contributed dominantly to the enhanced cytotoxicity observed under the "dynamic" exposure conditions, while the shear stress caused by these slowly flowing fluids (i.e., flow rates of 6 and $30{\mu}L/h$) had only a minor influence on the observed enhancement in cytotoxicity.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.336-339
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• 2007

The enhanced control of OLED deposition processes by Organic Vapor Phase Deposition $(OVPD^{(R)})$ is discussed. $OVPD^{(R)}$ opens a wide space of process control parameters. It allows the accurate and individual control of deposition layer properties like morphology and precise mixing of multi component layers (co-deposition) in comparison to conventional deposition manufacturing processes like e. g. VTE (vacuum thermal evaporation).

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.159-160
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• 2006

$AgGaSe_2$ single crystal thin films grown by using hot wall epitaxy (HWE) system. The single crystal thin films were investigated by photoluminescence and double crystal X-ray diffraction(DCXD) measurement. From the photoluminescence measurement of $AgGaSe_2$ single crystal thin film, we observed free excition ($E_x$) observable only in high quality crystal and neutral bound exciton ($D^{\circ}$,X) having very strong peak intensity. And, the full width at hall maximum and binding energy of neutral donor bound excition were 8 meV and 14.1 meV, respectively. By Haynes rule, an activation energy of impurity was 141 meV.

• Bulletin of the Korean Chemical Society
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• 제32권9호
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• pp.3433-3436
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• 2011

Some of metal nanoparticles have the potential for use as colorimetric assays for estimating solution properties, such as pH and temperature due to localized surface plasmon (LSP) phenomena. This report describes the use of silver nanoparticles (AgNP) conjugated with cytochrome c (Cyt c) for the colorimetric determination of solution pHs. When the pH of a solution decreases, the Cyt c immobilized on the AgNP undergoes a conformational change, leading to a decrease in the interparticle distance between Cyt c-AgNP probes and consequent red-shift in LSP. As a result, the color of the Cyt c-AgNP probe solution changes from yellow to red and finally to a grayish blue in the pH range from 11 to 3. This gradual color change can be used to determine the pH of a solution over a wide pH range, compared to other colorimetric methods that use gold nanoparticles.

• The Korean Journal of Physiology and Pharmacology
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• 제1권4호
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• pp.345-353
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• 1997

The effects of crude saponin (SAP) and alkaloid (ALK) fractions of Panax ginseng C.A. Meyer on the detrimental effects of electroconvulsive shock (ECS) and scopolamine on passive avoidance response (PAR) were studied in male Sprague-Dawley rats, referring their effects on the neuronal injury and plasticity of hippocampus in response to electrolytic lesion of left entorhinal cortex (ECL). The detrimental ECS effect on PAR was attenuated by pre- and post-treatments with SAP and ALK, respectively, or by pretreatment with aminoguanidine (AG), an inhibitor of diamine oxidase and NO synthase. And the detrimental scopolamine effect on PAR was also inhibited by pre-treatment with ALK or AG, and by post- treatment with SAP or ALK, respectively. On the 7th day after ECL, the brain sections stained by cresyl violet and by acetylcholinesterase (AChE) histochemistry, respectively, showed the chromatolysis and numeral decrease of neurons and the reduction of AChE reactivity in the hippocampus CA1 area and to a lesser extent, in the dentate gyrus. The neuronal cell death of the CA1 area was significantly reduced by SAP, ALK, or AG, and the reduction of AChE reactivity was significantly attenuated by SAP or ALK and to a lesser extent by AG. These results suggests that the protective effect of ginseng SAP and ALK fractions on ECS- or scopolamine-induced impairment of PAR may be ascribed in part to preservation of hippocampal neurons, particularly cholinergic neurons.

• Journal of Acupuncture Research
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• 제35권1호
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• pp.21-27
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• 2018

Background: Examination of the effects of deer antler, old antler, and antler glue on postmenopausal osteoporosis in an ovariectomized Sprague-Dawley rat model. Methods: The study involved 7 experimental groups; SHAM (sham-operated rats), OVX (ovariectomized rats), E2 (ovariectomized rats with estradiol $10{\mu}g/kg$ daily, orally), DA (ovariectomized rats with deer antler extract 5.83 mg/kg), OA (ovariectomized rats with old antler extract 3.8 mg/kg), low-AG (ovariectomized rats with low dose of antler glue powder 12.5 mg/kg), high-AG (ovariectomized rats with high dose of antler glue powder 37.5 mg/kg). After 6 weeks of treatment, body weight, blood calcium, phosphorus, estradiol, liver [alkaline phosphatase (ALP), aspartate transaminase (AST), alanine transaminase (ALT)] and kidney [blood urea nitrogen (BUN)/creatinine ratio] function, and femoral bone mineral density (BMD) were measured. Results: The body weights of DA, OA, low-AG, and high-AG groups did not significantly differ from OVX group. Blood estradiol levels were significantly increased in the DA, low-AG, and high-AG groups compared to the OVX group. Blood calcium, phosphorus, ALP, AST, and ALT levels and BUN/creatinine ratio did not show significant changes in the DA, OA, low-AG, and high-AG groups. BMDs of the femur, and femoral head and neck were significantly increased in the low-AG group. In the OA group, the BMD of the femoral head and neck was significantly increased. Conclusion: Treatment with deer antler, or antler glue for 6 weeks was effective for increasing estradiol and femoral BMD in ovariectomized rats, suggesting that this may be of therapeutic benefit for osteoporosis.

• 한국전기전자재료학회논문지
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• 제17권6호
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• pp.678-682
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• 2004

Generally Bi-2223/Ag tapes have a broad S/N transition region and their sheath is a good electric conductor. In this study, the current distribution between superconductor and metal sheath in HTS tapes were investigated. AC with its peak value above 10 times $I_{c}$ was applied to HTS tapes for around 6 cycles and V-I characteristics were measured. Using the resistance of the sheath and V-I curves, the current distribution between superconductor and metal sheath was calculated. When 150 $A_{p}$ was applied, more than 2/3 of the current flows through superconductor. However, in the case of 304 $A_{p}$, most of the applied current came to flow through the metal sheath at the 6th cycle.e.e.e.

• Biomolecules & Therapeutics
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• 제22권1호
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• pp.27-34
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• 2014

Curcumin is naturally occurring polyphenolic compound found in turmeric and has many pharmacological activities. The present study was undertaken to evaluate anti-allergic inflammatory activity of curcumin, and to investigate its inhibitory mechanisms in immunoglobulin E (IgE)/Ag-induced mouse bone marrow-derived mast cells (BMMCs) and in a mouse model of IgE/Ag-mediated passive systemic anaphylaxis (PSA). Curcumin inhibited cyclooxygenase-2 (COX-2) dependent prostaglandin $D_2$ ($PGD_2$) and 5-lipoxygenase (5-LO) dependent leukotriene $C_4$ ($LTC_4$) generation dose-dependently in BMMCs. To probe the mechanism involved, we assessed the effects of curcumin on the phosphorylation of Syk and its downstream signal molecules. Curcumin inhibited intracellular $Ca^{2+}$ influx via phospholipase $C{\gamma}1$ ($PLC{\gamma}1$) activation and the phosphorylation of mitogen-activated protein kinases (MAPKs) and the nuclear factor-${\kappa}B$ (NF-${\kappa}B$) pathway. Furthermore, the oral administration of curcumin significantly attenuated IgE/Ag-induced PSA, as determined by serum $LTC_4$, $PGD_2$, and histamine levels. Taken together, this study shows that curcumin offers a basis for drug development for the treatment of allergic inflammatory diseases.

• 한국재료학회지
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• 제11권5호
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• pp.419-426
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• 2001

AgGaSe$_2$ 단결정 박막은 수평 전기로에서 합성한 $AgGaSe_2$ 다결정을 증발원으로 하여, hot wall epitaxy (HWE) 방법으로 증발원과 기판 (반절연성-GaAs(100)) 의 온도를 각각 $630^{\circ}C$, $420^{\circ}C$로 고정하여 박막 결정 성장을 하였다. 10K에서 측정한 광발광 excition 스펙트럼과 이중결정 X-선 요동곡선 (DCRC) 의 반치폭 (FWHM )을 분석하여 단결정 박막의 최적 성장 조건을 얻었다. Hall효과는 van der Pauw 방법에 의해 측정되었으며, 온도에 의존하는 운반자 농도와 이동도는 293k에서 각각 4.89$\times$$10^{ 16}$/㎤, 129$\textrm{cm}^2$/V.s였다. 광전류 봉우리의 10K에서 단파장대의 가전자대 갈라짐 (splitting)에 의해서 측정된 $\Delta$C$_{r}$ (crystal field splitting)은 0.1762eV, $$\Delta$S_{o}$ (spin orbit splitting)는 0.2494eV였다 10K의 광발광 측정으로부터 고풍질의 결정에서 볼 수 있는 free excitors과 매우 강한 세기의 중성 주개 bound excitors등의 피크가 관찰되었다. 이때 중성 주개 bound ekciton의 반치폭과 결합에너지는 각각 BmeV와 14.1meV였다. 또한 Haynes rule에 의해 구한 불순물의 활성화 에너지는 141meV였다.rule에 의해 구한 불순물의 활성화 에너지는 141meV였다.

• Journal of Nutrition and Health
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• 제52권3호
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• pp.250-257
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• 2019

본 연구에서는 섬쑥부쟁이 (Aster glehni)와 쑥부쟁이(Aster yomena)의 항산화 효과 및 항비만 효과를 검정하기 하여 물 (-W)과 에탄올 (-E)추출물을 이용하여 실험을 실히 하였다. 각 추출물을 총 페놀 및 총 플라보노이드를 함량을 분석하고 DPPH와 $ABTS^+$를 이용하여 항산화 활성을 비교 분석하였다. 또한 총 페놀 및 총 플라보노이드를 함량과 항산화 활성의 상관관계도 분석하였다. 항산화 물질로 알려진 총 페놀과 플라보노이드 함량은 섬쑥부쟁이의 70% 주정 추출물에서 각각 45.42 mg/g와 40.32 mg/g으로 다른 추출물에 비해 높은 함량을 나타내었다. 항산화 효과의 경우 또한 $ABTS^+$의 $IC_{50}$값이 섬쑥부쟁이의 70% 주정 추출물에서 $30.1{\mu}g/mL$로 가장 우수하였다. 총 페놀 및 총 플라보노이드를 함량과 항산화 활성의 상관관계도 유의적으로 통계처리 되어 추출물의 함량이 항산화 활성에 영향이 있다는 것을 보여주었다. 또한, 섬쑥부쟁이와 쑥부쟁이의 항비만 효능 평가를 위하여 지방세포인 3T3-L1의 분화 억제를 확인하였다. 추출물을 농도별로 처리하여 지방분화를 Oli-Red O 염색약으로 염색하여 비교하여 보았을 때, 섬쑥부쟁이의 물 추출물에서 70.49%의 가장 낮은 지질 축적율을 나타내었다. 이상의 결과에서, 섬쑥부쟁이의 총 페놀 및 총 플라보노이드를 함량, 항산화 활성과 지방분화 억제 활성이 우수하게 나타났다. 이에 본 연구결과를 바탕으로 섬쑥부쟁이가 안정성이 검증된 항비만 기능성 식품이나 의약품 소재로써 활용될 수 있을 것으로 기대된다.