• Natural Product Sciences
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• v.22 no.2
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• pp.111-116
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• 2016

Phytochemical investigation of the stems of Pueraria lobata (Wild) Ohwi (Leguminosae), led to the isolation of eighteen known compounds: ${\beta}$-amyrone (1), (+)-pinoresinol (2), (+)-syringaresinol (3) $(+)-syringaresinol-O-{\beta}-{\small{D}}-glucoside$ (4), (+)-lariciresinol (5), (-)-tuberosin (6), naringenin (7), liquiritigenin (8), isoliquiritigenin (9) genistein (10), daidzein (11) daidzin (12) daidzein 4',7-diglucoside (13) 2,4,4'-trihydroxy deoxybenzoin (14), S-(+)-1-hydroxy-3-(4-hydroxyphenyl)-1-(4-hydroxy-2-methoxy-phenyl)propan-2-one (15), methyl $2-O-{\beta}-{\small{D}}-glucopyranosylbenzoate$ (16), pyromeconic acid $3-O-{\beta}-{\small{D}}-glucopyranoside$ 6'- (O-4''-hydroxy-3-methoxybenzoate) (17), and allantion (18). The chemical structures of these compounds were elucidated from spectroscopic data and by comparison of those data with previously published results. The effects of isolated compounds on mushroom tyrosinase enzymatic activity were screened. The results indicated that, chloroform extract of P. lobata stems turned out to be having tyrosinase inhibitory effect, and only compounds 5, 8, 9, and 11 showed enzyme inhibitory activity, with $IC_{50}$ values of $21.49{\pm}4.44$, $25.24{\pm}6.79$, $4.85{\pm}2.29$, and $17.50{\pm}1.29{\mu}M$, respectively, in comparison with these of positive control, kojic acid ($IC_{50}\;12.28{\pm}2.72{\mu}M$). The results suggest that P. lobata stems extract as well as its chemical components may represent as potential candidates for tyrosinase inhibitors.

• Tuberculosis and Respiratory Diseases
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• v.67 no.6
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• pp.536-544
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• 2009

Background: A combination of salmeterol and fluticasone propionate (SFC) and tiotropium bromide (TIO) is commonly prescribed for COPD patients but there is little data on their effectiveness, particularly in COPD patients with bronchial hyperresponsiveness. This study compared the spirometric improvement based on the change in $FEV_1$, $FEV_1$/FVC, and IC as well as the clinical outcomes of the therapeutic strategies with SFC and TIO versus the individual components in patients with severe COPD and bronchial hyperresponsiveness. Methods: This study examined the spirometric data and clinical outcomes of 214 patients with COPD and hyperresponsiveness, who were divided into three groups according to the therapeutic regimen (TIO only, SFC only, and a triple therapy regimen). Results: All regimen groups showed early improvement in the $FEV_1$ and IC (at 3- and 6 months after treatment). However, long-term beneficial effects were observed only in the SFC group (at 24 months after treatment). However, these beneficial effects decreased after a 36-month follow up. In all spirometric results, the 12-, 24-, and 36-months data showed a similar degree of improvement in the three groups. The triple therapy group showed higher St. George's Respiratory Questionnaire scores and lower acute exacerbations and hospitalization. Conclusion: SFC can be a more important component in the pharmacological treatment of severe COPD patients with hyperresponsiveness than TIO, particularly in the spirometric and clinical outcomes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.4
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• pp.518-523
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• 2016

This study investigated the nutritional components and antioxidant activity of dry bitter melon (Momordica charantia L.). The moisture, crude protein, crude fat, crude ash, carbohydrate, and ascorbic acid contents of dry bitter melon were 6.10%, 3.31%, 1.08%, 2.31%, 87.20%, and 908.84 mg/100 g, respectively. Potassium was the most abundant mineral, followed by Mg, P, Na, Ca, Zn, Cu, and Mn, which means dry bitter melon was an alkali material. Regarding amino acid contents, dry bitter melon was rich in arginine, urea, asparagine, ${\gamma}-aminobutyric$ acid, and alanine. Total polyphenol and total flavonoid contents of dry bitter melon extract were 36.08 mg gallic acid equivalents/extract g and 15.66 mg tannic acid equivalents/extract g, respectively. The $IC_{50}$ value for 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity was 9.81 mg/mL for dry bitter melon ethanol extracts.

• Journal of the Institute of Convergence Signal Processing
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• v.13 no.1
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• pp.39-43
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• 2012

60GHz band RF transceiver was made with the NRD waveguide structure for the point- to-point communication. A dielectric line that of comprising NRD waveguide was the milling process was not easy because a material gets soft, and also compression and expansion according to a temperature were serious, so this line was not suitable for the device in which the resonance characteristic was important. In addition, the thing for comprising amplification module was difficult in the NRD waveguide structure. In this paper, a way in which to overcome mentioned in upper part, the transceiver was made by below technology. Components in which the resonance characteristic was not important were made with the NRD waveguide hybrid IC, and components in which the resonance characteristic was important were made with waveguide. An amplifier packaged and modularizing the bare chip, it equipped at the NRD waveguide within. Manufactured transceiver communicated with FDD method, and it had 10dBm output power, and -60dBm minimum receive sensitivity.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.8
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• pp.120-128
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• 2004

The impulse between launch vehicle and atmosphere can generate a lot of noise and vibration during the process of launching a satellite. Structurally, the electronic equipment of a satellite consists of an aluminum case containing PCB. Each PCB has resistors and IC. Noise and vibration of the wide frequency band are transferred to the inside of fairing, subsequently creating vibration of the electronic equipment of the satellite. In this situation, random vibration can cause malfunctioning of the electronic equipment of the device. Furthermore, when the frequency of random vibration meets with natural frequency of PCB, fatigue fracture may occur in the part of solder joint. The launching environment, thus, needs to be carefully considered when designing the electronic equipment of a satellite. In general, the safety of the electronic equipment is supposed to be related to the natural frequency, shapes of mode and dynamic deflection of PCB in the electronic equipment. Structural vibration analysis of PCB and its electronic components can be performed using either FEM or vibration test. In this study, the natural frequency and dynamic deflection of PCB are measured by FEM, and the safety of the electronic components of PCB is evaluated according to the results. This study presents a unique method for finite element modeling and analysis of PCB and its electronic components. The results of FEA are verified by vibration test. The method proposed herein may be applicable to various designs ranging from the electronic equipments of a satellite to home electronics.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.12
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• pp.1093-1098
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• 2012

Commercial Off the Shelf(COTS) Integrated circuits(ICs) are being increasingly considered for use in space and military applications. Therefore, There is a need to implement standard tests and requirements to ensure reliability of COTS ICs. This paper presents an overview of the ICs screen procedure and methods under the European Cooperation for Space Standardization (ECSS) and Tests Method Standard Microcircuits (MIL-STD-883). We describes the COTS ICs screen test guidelines that are mainly focused after encapsulating. In addition, COTS linear bipolar IC is investigated to evaluate the reliability requirements. The experiment results showed that COTS IC is satisfied with high reliability requirements.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.4
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• pp.405-414
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• 2016

IC-implementations provide high performance for solving the high computational cost of pattern matching but have relative low flexibility for satisfying different applications. In this paper, we report an associative memory architecture for k nearest neighbor (KNN) search, which is one of the most basic algorithms in pattern matching. The designed architecture features reconfigurable vector-component parallelism enabled by programmable switching circuits between vector components, and a dedicated majority vote circuit. In addition, the main time-consuming part of KNN is solved by a clock mapping concept based weighted frequency dividers that drastically reduce the in principle exponential increase of the worst-case search-clock number with the bit width of vector components to only a linear increase. A test chip in 180 nm CMOS technology, which has 32 rows, 8 parallel 8-bit vector-components in each row, consumes altogether in peak 61.4 mW and only 11.9 mW for nearest squared Euclidean distance search (at 45.58 MHz and 1.8 V).

• Preventive Nutrition and Food Science
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• v.3 no.4
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• pp.315-319
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• 1998

Previously, the methanolic extract of Paeonia moutan seeds was found to potently inhibit soybean lipoxy-genase (SLO). Hence to isolate SLO inhibitor, the defattd methaniolic extract of the seeds was consecutively partitioned wiht ether, ethyl acetate,n-butanol ,adn water. The ether souble fraction showing strong inhibitory activity against SLO was further fractionated into a strongly acidic, a weakly acidic, and a neutral fractions. The strongly acidic components of the ether extract were successively subjected to chromatography on a silica gel, Sephadex LH-20, and preparative HPLC. Four phenolic compounds were isolated , and twio of them showing a strong SLO inhibition activity were identified as luteolin (IC50=2.32$\mu\textrm{g}$/ml) and 5,6,4'-trihydroxy-7,3'- dimethoxylflavone (IC50=0.31$\mu\textrm{g}$/ml) by UV, IR, 1H-& 13C-NMR, and MS spectroscopy. In addition, two flavonoids showed significantly antioxidative activity as strong as that of of $\alpha$-tocopherol (p<0.05) in the autoxidation system of linoleic acid. These results suggest that luteolin and 5,6,4'-trihydroxy-7,3'-dimethoxy-flavone may be used as a potential source of anti-inflammatory agents with antioxidative activity.

• IEIE Transactions on Smart Processing and Computing
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• v.5 no.3
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• pp.207-214
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• 2016

Optical communication systems are rapidly spread following increases in data traffic. In this work, a 32-Gb/s inductorless output buffer circuit with adjustable pre-emphasis is proposed. The proposed circuit consists of an output buffer circuit and an emphasis circuit. The emphasis circuit emphasizes the high frequency components and adds the characteristics of the output buffer circuit. We proposed a design method using a small-signal equivalent-circuit model and designed the compensation characteristics with a 65-nm CMOS process in detail using HSPICE simulation. We also realized adjustable emphasis characteristics by controlling the voltage. To confirm the advantages of the proposed circuit and the design method, we fabricated an output buffer IC with adjustable pre-emphasis. We measured the jitter and eye height with a 32-Gb/s input using the IC. Measurement results of double-emphasis showed that the jitter was 14% lower, and the eye height was 59% larger than single-emphasis, indicating that our proposed configuration can be applied to the design of an output buffer circuit for higher operation speed.

• Biomolecules & Therapeutics
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• v.17 no.1
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• pp.86-91
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• 2009

In our ongoing search for biological components from the Korea endemic plants, the MeOH extract of Ailanthus altissima leaves (Simaroubaceae) showed cyclooxygenase-2 (COX-2) and 5-lipoxygenase (5-LOX) dual inhibitory activity by assessing their effects on the production of prostaglandin $D_2$ ($PGD_2$) and leukotriene $C_4$ ($LTC_4$) in mouse bone marrow-derived mast cells (BMMCs). In further study, eight compounds, squalene (1), ${\beta}$-sitosterol (2), scopoletin (3), quercetin (4), luteolin (5), astragalin (6), scopolin (7), and daucosterol (8) were isolated, the chemical structures were elucidated on the basis of physicochemical and spectroscopic data and by comparison with those of published literatures. Among the compounds, 2, 4, and 5 strongly inhibited both the COX-2-dependent PGD2 generation with $IC_{50}$ values of 2.6, 7.3 and 2.5 ${\mu}M$, respectively and the generation of $LTC_4$ in the 5-LOX dependent phase with $IC_{50}$ values of 2.0, 5.1 and 1.8 ${\mu}M$, respectively, which suggest that the anti-inflammatory activity of A. altissima might occur in part via the inhibition of both $PGD_2$ and $LTC_4$ generation by 2, 4 and 5.