• Journal of Life Science
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• v.22 no.9
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• pp.1180-1186
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• 2012

The purpose of this study was to investigate the effect of exercise preconditioning (EPC) on nerve growth factor (NGF), synapsin I, and choline acetyltransferase (ChAT) in the hippocampus of rats subjected to social isolation (SI). We randomly assigned four groups of male Sprague-Dawley (SD) rats (n=32) to the following treatments: GC: group housing control; IC: isolation control; GE: group housing exercise; IE: isolation exercise (n=8 each group). The rats underwent EPC 5 days a week for 8 weeks, and the speed of the treadmill was gradually increased (grade $0^{\circ}C$). After EPC, they were immediately subjected to SI for 8 weeks. The results showed that the protein levels of NGF, synapsin I, and ChAT in the hippocampus were significantly decreased in the IC group (p<0.05) compared with the GC group. However, these protein levels were significantly higher in the IE group (p<0.05). These results show that EPC may buffer the decline of function in the hippocampus by ameliorating the reduction in NGF, synapsin I, and ChAT induced by SI.

• Archives of Pharmacal Research
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• v.25 no.2
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• pp.151-153
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• 2002

Three pseudoguaianolide type sesquiterpenes, bigelovin(1), 2,3-dihydroaromaticin (2), and ergolide (3) were isolated as inhibitory constituents against inducible nitric oxide synthase (iNOS) from the flowers of Inula britannica var. chinensis. Bigelovin (1) exhibited a highly potent inhibitory activity on lipopolysaccharide (LPS)-induced iNOS in murine macrophage RAW 264.7 cells with an $IC_{50}$ value of 0.46 mM, which is about 8 times more potent than the known selective inhibitor of iNOS, $L-N^6-(1-iminoethyl)Iysine{\;}(IC_{50}{\;}3.49{\;}{\mu}M)$. 2,3-Dihydroaromaticin (2) and ergolide (3) also exhibited potent inhibitory activities on LPS-induced iNOS with $IC_{50}$ values of 1.05 and $0.69{\;}{\mu}M$, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.57 no.3
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• pp.209-215
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• 2024

Ishige foliacea belongs to class Phaeophyceae and family Ishigeaceae. This study investigated the physiological activities of the Korean marine algae I. foliacea. Its solvent extracts were prepared with 70% ethanol, 80% methanol, and distilled water. The ethanol and methanol extracts had higher α-glucosidase (half-maximal inhibitory concentration, IC₅₀: 0.67-0.73 mg/mL), xanthine oxidase (IC₅₀: 0.25-0.28 mg/mL), and angiotensin-converting enzyme (IC₅₀: 25.29-38.28 ㎍/mL) inhibitory activities than those of the water extract. The ethanol and methanol extracts possessed high acetylcholinesterase inhibitory activity (IC₅₀: 0.78c0.97 mg/mL). Conversely, the water extract exhibited the highest β-secretase inhibitory activity (IC₅₀: 0.48 mg/mL). These results indicate that I. foliacea may be useful as a functional substance in food and pharmaceuticals with anti-diabetic, anti-gout, anti-hypertension, and anti-dementia properties.

• Journal of Applied Reliability
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• v.7 no.1
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• pp.1-11
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• 2007

This paper presents a derating design approach for reliability improvement of a regulator IC. The IC is usually used in SMPS. The main failure mechanism of interest is voltage drop due to the package delamination mainly caused by two stresses, i.e. temperature and current. The lifetime under stresses is modeled as a function of stresses and time using accelerating life testings. Quantitative and qualitative variation in lifetime according to stress variations are investigated using the modeled lifetime. Stress levels would be determined to achieve required reliability levels in the aspect of derating design for reliability.

• Journal of the Korean Institute of Telematics and Electronics
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• v.13 no.3
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• pp.22-27
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• 1976

For linear IC design, one has to know the epi thickness, resistivity, and structure of buried island inserted between epi and substrate because the mask structure can only be changed for linear IC consisted of various type of transistors to be made for desired specific function. The interrelation of IC operational and saturation voltages with epi resistivity, theckness and divice structure are studied and presented in graphic forms so that IC design engineers can utilize them.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.1
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• pp.135-144
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• 2021

This study investigates the impact of gender diversity on the board of directors on corporate intellectual capital (IC) disclosure in Indonesia. For the study purpose, the sample was divided into two sections, i.e., companies with large capitalizations and companies with small capitalizations. A paired T-test was used to observe significant changes in the disclosure level between period and type of firm. Using linear regression analysis, the influence of gender diversity and other variables on IC disclosure was examined. The findings show that IC disclosure varies for large and small companies. The level of IC disclosure in large companies was stronger than in small companies. The results of the multivariate analysis showed that the profitability, leverage, ownership, and type of business of the company significantly affect IC disclosure. For companies with large capitalization, the presence of women directors on corporate boards or gender diversity on corporate boards does not impact IC disclosure. This is because the Indonesia Stock Exchange (IDX) does not insist on IC disclosure. However, for small companies, the existence of gender diversity has a significant effect on IC disclosure. The findings of this study suggest that policymakers and standard makers must consider the inclusion of IC disclosure on the annual report as mandatory.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.9
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• pp.81-86
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• 2000

This paper was carried out to investigate the characteristics of interlaminar fracture toughness of foam core sandwich structures under opening loading mode by using the double cantilever beam (DCB) specimens in Carbon/Epoxy and foam core composites. instead of using symmetric geometry of DCB specimen non-symmetric DCB specimen was used to calculate the interlaminar fracture toughness. Three approaches for calculating the energy release rate({{{{ {G }_{IC } }}}}) were compared. Fracture toughness of foam core sandwich structures by autoclave vacuum bagging and hotpress were compared and analyzed. Experiment nonlinear beam bending FEM method were performed. Suggested bonding surface compensation and equivalent area inertia moment was used to calculate the energy release rate in nonlinear analytical results. The conclusions among experimental nonlinear analytical and FEM results was observed. The vacuum bagging method was shown to be able to substitute method in stead of autoclave without serious loss of Mode I energy release rate({{{{ {G }_{IC }}}}}) to be able to substitute method in stead of autoclave without serious loss of Mode I energy release rate({{{{ {G }_{IC }}}}}).

• Korean Journal of Food Science and Technology
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• v.39 no.1
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• pp.77-82
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• 2007

From the total methanolic extract of Chrysanthemum coronarium L. var. spatiosum (Compositae), nitrite scavenging ability and superoxide dismutase (SOD)-like activity were analyzed as antioxidative characteristics. After successive partitioning with chloroform, n-butanol, and water, the chloroform fraction showed the most significant nitrite scavenging ability with an $IC_{50}$ value of 39 ppm compared with the values of vitamin C and chlorogenic acid, 15 ppm and 36 ppm, respectively. The active fraction was subjected to silica gel and Sephadex LH-20 column chromatography, and the compound was isolated and identified as ${\beta}-sitosterol-O-{\beta}-D-glucoside$ using $^{1}H-NMR$ and $^{13}C-NMR$ spectral data. The glucoside was further hydrolyzed and confirmed as a glycosylated ${\beta}-sitosterol$. The compound and its aglycone, ${\beta}-sitosterol$, showed different nitrite scavenging and SOD-like activity. The $IC_{50}$ value of nitrite scavenging ability of the compound was 335 ppm at pH 1.5, while that of its aglycone was 41 ppm. As for the SOD-like activity, the $EC_{50}$ values of the sterol and the glucoside were 1,291 ppm and >2,000 ppm, respectively, compared with those of vitamin C and chlorogenic acid, 38 ppm and 449 ppm, respectively.

• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.123-126
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• 2000

본 논문에서는 음성 신호 처리 IC를 제어하는 임베디드 시스템을 Micro-controller를 이용하여 설계하고 제어 프로그램을 구성/제작하여 기능을 분석한다. 선택한 음성처리용 IC 중에서 ISD2560은 내장된 EEPROM에, T6668은 외부에 D-RAM을 연결하여 음성 메시지를 저장하고 있다. PIC16F84는 음성데이터의 입출력과 저장과 재생, 초기화를 위한 회로의 동작과 순서 제어, 시작과 종료하는 메모리 번지의 생성과 같은 제어 프로그램을 수행한다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.10a
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• pp.297-298
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• 2006