• 한국식물학회:학술대회논문집
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• 한국식물학회 2002년도 춘계학술발표대회:발표눈문요지록
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• pp.73-82
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• 2002

The committing step in Met and S-adenosyl-L-methionine (SAM) synthesis is catalyzed by cystathionine ${\gamma}$ -synthase (CGS). Transgenic Arabidopsis thaliana overexpressing CGS under control of 35S promoter show increased soluble Met and its metabolite S-methylmethionine, but only at specific stages of development. CGS-overexpressing seedlings are resistant to ethionine. Similar results were obtained with transgenic potato plants overexpressing Arabidopsis CGS. Several of the transgenic lines show silencing of CGS resulting in deformed p]ants with a reduced capacity for reproductive growth similar as transgenic plants by antisense RNA (CGS[-]). Exogenous feeding of Met to the CGS[-] and CGS[+] silenced plants partially restores their growth. Similar morphological deformities are observed in plants cosuppressed for SAM synthetase, even though such plants accumulate 250 fold more soluble Met than wild type and they overexpress CGS. The results suggest that the abnormalities associated with CGS and SAM synthetase silencing are due in part to a reduced ability to produce SAM, and that SAM may be a regulator of CGS expression.

• 한국철도학회논문집
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• 제9권1호
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• pp.63-68
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• 2006

This paper proposes a fast Fourier transform(FFT)-based spectral analysis method(SAM) for the dynamic responses of the linear discrete dynamic models with non-proportional damping. The SAM was developed by using discrete Fourier transform(DFT)-theory. To verify the proposed SAM, a three-DOF system with non-proportional viscous damping is considered as an illustrative example. The present SAM is evaluated by comparing the dynamic responses obtained by SAM with those obtained by Runge-Kutta method.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -3
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• pp.1559-1562
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• 2002

This paper describes a 0.13um ultra-high speed 1Mb CMOS SRAM macro with 1.7ns access time. It achieves ultra-high speed operation using two novel approaches. First, it uses process insensitive sense amplifier (Double-Equalized Sense Amplifier) which improves voltage offset by about 10 percent. Secondly, it uses new replica-based sense amplifier driver which improves bit- line evaluation time by about 10 percent compared to the conventional technique. The various memory macros can be generated automatically by using a compiler, word-bit size from 64kb to 1 Mb including repairable redundancy circuits.

• Journal of applied mathematics & informatics
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• 제9권1호
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• pp.101-124
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• 2002

The convergence rate of a numerical procedure barred on Schwarz Alternating Method (SAM) for solving elliptic boundary value problems (BVP's) depends on the selection of the interface conditions applied on the interior boundaries of the overlapping subdomains. It hee been observed that the Robin condition(mixed interface condition), controlled by a parameter, can optimize SAM's convergence rate. Since the convergence rate is very sensitive to the parameter, Tang[17] suggested another interface condition called over-determined interface condition. Based on the over-determined interface condition, we formulate the two-layer multi-parameterized SAM. For the SAM and the one-dimensional elliptic model BVP's, we determine analytically the optimal values of the parameters. For the two-dimensional elliptic BVP's , we also formulate the two-layer multi-parameterized SAM and suggest a choice of multi-parameter to produce good convergence rate .

• Tribology and Lubricants
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• 제17권4호
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• pp.276-282
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• 2001

Nano adhesion between SPM (scanning probe microscope) tips and 075 (octadecyltrichlorosilane) SAM (self-assembled monolayer) was experimentally studied. Tests were performed to measure the nano adhesion and friction in both AFM(atomic force microscope) and LFM(lateral force microscope) modes in various conditions of relative humidity. OTS SAM was formed on Si-wafer (100) surfaces, and Si$_3$N$_4$ tips of different radius of curvature were used. When the surface was hydrophobic, the adhesion and friction forces were found lower than those of bare Si-wafer. Results also showed that micro-adhesion force increased as the relative humidity and the tip radius of curvature increased. The main parameter for affecting the micro-adhesion was found absorbed humidity on the contact surface. These results were discussed with the JKR model and a capillary force caused by absorbed water.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1996년도 춘계학술대회
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• pp.244-244
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• 1996

In previous studies we reported that the levels of RBC, hemoglobulin and hematocrit in SAM Rl and SAM P6 were increased significantly from 7 day after oral administration of the pilose antler extract, 5g/kg/day, and were lasted during the study. Therefore, this study was performed to elucidate mechanism of erythropoietic action by the extract administration. SAM Rl and SAM P6 were chosen as experimental animals. At age of 12 weeks, pilose antler extract were given 0.3 and 5 g/kg/day (p.o.) each for 0, 7 and 14 days in both animals. Complete blood cells (CBC) such as WBC, lymphocytes, monocytes, granulocytes, RBC, hemoglobulin, and hematocrit were counted. And plasma concentration of erythropoietin (EPO) which is the major regulator of erythropoiesis was measured using $\^$125/I-antierythropoietin IgG. Ferritin concentration in plasma was also analyzed.

• 대한의생명과학회지
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• 제29권3호
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• pp.152-158
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• 2023

The aim of this study is to investigate the analgesic effects of Syneilesis aconitifolia Maxim. extract (SAM). We evaluated analgesic effects of SAM on animal pain model. Male SD rats were administered intra-orally with SAM according to prescribed dosage. During 7 days. After 7 days later, serum TNF-α, IL-1β, and IL-6 levels were measured by ELISA. In our experiment, administration of SAM decreased IL-1β, IL-6, TNF-α and PGE2 level in serum. Furthermore, it was confirmed that allodynia was relieved in evaluation of pain behavior. It was confirmed that administration of SAM reduces nociceptive pain by reducing nociceptive stimuli by acting as an anti-inflammatory drug.

• 공업화학
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• 제8권5호
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• pp.784-789
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• 1997

전도성 고분자인 폴리피롤(PPy)을 전해질로 하는 알루미늄(Al)고체전해 캐패시터를 제작하기 위하여 알루미늄 산화피막($Al_2O_3$) 위에 화학산화중합(CP)법으로 얇은 PPy층을 형성시키고, 이 층을 양극으로 이용하여 피롤(Py)을 전해산화중합(EP)시켰다. 캐패시터 특성에 영향을 미치는 중합조건을 조사한 결과, 지지전해질로서 sodium p-toluenesulfonate (TsONa)를 사용하고, 소자당 2.0~4.0 mA의 정전류를 인가, 전해중합 후 제작한 캐패시터의 전기적 특성 및 임피던스 특성이 가장 우수하였다.

• Journal of Microbiology and Biotechnology
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• 제28권7호
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• pp.1105-1111
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• 2018

The flavin-dependent monooxygenase Sam5 was previously reported to be a bifunctional hydroxylase with coumarate 3-hydroxylase and resveratrol 3'-hydroxylase activities. In this article, we showed the Sam5 enzyme has 3'-hydroxylation activities for methylated resveratrols (pinostilbene and pterostilbene), hydroxylated resveratrol (oxyresveratrol), and glycosylated resveratrol (piceid) as substrates. However, piceid, a glycone-type stilbene used as a substrate for bioconversion experiments with the Sam5 enzyme expressed in Escherichia coli, did not convert to the hydroxylated compound astringin, but it was converted by in vitro enzyme reactions. Finally, we report a novel catalytic activity of Sam5 monooxygenase for the synthesis of piceatannol derivatives, 3'-hydroxylated stilbene compounds. Development of this bioproduction method for the hydroxylation of stilbenes is challenging because of the difficulty in expressing P450-type hydroxylase in E. coli and regiospecific chemical synthesis.

• 한국전기전자재료학회논문지
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• 제19권6호
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• pp.563-567
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• 2006

Indium tin oxide (ITO) used as an electrode in organic light emitting diodes (OLEDs) and organic thin film transistors (OTFTs) was modified by a self-assembled monolayer (SAM). For device fabrication, surface of the ITO was modified by immersion in a solution including various phosphonic acid at room temperature in order to increase work function of an electrode. The work function of ITO with SAM was measured by Kelvin probe. Work function increase of 0.88 eV was observed in ITO with various SAM. Therefore, ohmic contact is achieved in an interface between ITO and organic semiconductors (pentacene). We analyzed the origin of work function increase of ITO with SAM by X-ray photoelectron spectroscopy. We confirmed that increase of oxygen bonding energy attributed to increase the work function of ITO. These results suggested that ITO with the SAM gives a high possibility for high performance of OLEDS and OTFTs.