• The Korean Journal of Physiology
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• v.15 no.2
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• pp.83-89
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• 1981

This study was conducted to investigate the effect of the ingestion of rice and hamburger meals upon the plasma gastrin concentration in normal human subjects in Korea. Eight normal human subjects including male and female with the mean age of 28 years (range: 20-40 years) were studied. After an overnight(about 15 hrs) fast each subject ingested a rice meal and a hamburger meal on different days. The rice meal consisted of 250 g boiled rice, 50 g vegetables and 200 ml barley tea, corresponding to 6.8 g protein, 0.5 g fat and 81g carbohydrate and the hamburger meal consisted of 200 g hamburger, 50 g vegetables ana 200 ml milk, corresponding to 43 g protein, 43 g fat and 9 g carbohydrate. The venous blood samples were drawn before and after the ingestion of the test meal at the following times: -30, 0, 15, 30, 45, 60, 90, and 120 min, for measurement of gastrin by radioimmunoassay. The following results were obtained : 1) Plasma gastrin concentration in response to the ingestion of the rice or the hamburger meal increased significantly compared with the concentration in fasting state. 2) The increase of the plasma gastrin concentration after the hamburger meal was significantly higher than that after the rice meal. 3) There was a significant linear correlation between the postprandial peak plasma gastrin concentration after the rice meal and the concentration after the hamburger meal in each subject. It is inferred from the above results that a carbohydrate meal as well as a protein meal has a stimulatory effect on gastrin release in normal human subjects.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.12
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• pp.1753-1757
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• 2012

A new liquid chromatographic tandem mass spectrometric (LC-MS/MS) assay for the quantification of ginsenoside Rb1 in human plasma was developed and validated. The separation was performed on a Agilent C18 column ($4.6mm{\times}150mm$, particle size 5 ${\mu}m$) with a gradient elution of 0.1% formic acid in water and 0.1% formic acid in methanol and a flow rate of 0.9 mL/min. The analyte was determined using electrospray positive ionization mass spectrometry in the multiple reaction monitoring (MRM) mode (m/z 1131.714${\rightarrow}$365.303). Human plasma samples were extracted with acetone : water (50:50) by the liquid-liquid extraction method. The method was linear over the dynamic range of 10~500 ng/mL with a correlation coefficient of r=0.9995. The intra-and inter-day precision over the concentration range of ginsenoside Rb1 was lower than 5.8% (correlation of variance, CV), and the accuracy was between 96.0~104.6%. This LC-MS/MS assay of ginsenoside Rb1 in human plasma is applicable for quantification in a pharmacokinetic study.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.10
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• pp.1469-1477
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• 2014

This experiment was conducted to investigate the effects of dietary supplementation of magnesium sulfate ($MgSO_4$) during late gestation and lactation on sow and litter performance, fecal moisture, blood biochemistry parameters, immunoglobulin levels and milk composition in sows. Forty-eight sows ($Yorkshire{\times}Landrace$, 4th to 5th parity) were randomly allocated to 1 of 4 dietary treatments supplemented with 0, 200, 400, or 600 mg/kg $MgSO_4$ (n = 12). The experiment started on day 90 of gestation and continued through day 21 of lactation. Blood samples were collected on day 107 of gestation, day 0 (farrowing) and 21 (weaning) of lactation for the analyses of the blood biochemistry parameters and immunoglobulin levels. The colostrum and milk samples were obtained on day 0 and 14 of lactation, respectively. Fecal samples were collected from the sows on day 107 of gestation as well as day 7 and 20 of lactation to determine fecal moisture content. The results showed that the survival percentage of piglets and the litter weight at weaning were decreased linearly (p<0.05) and other parameters of the sow or litter performance were not influenced (p>0.05) by $MgSO_4$ supplementation. The fecal moisture content of the sows were increased (p<0.05) linearly as dietary $MgSO_4$ increased on day 7 and 20 of lactation. Supplementation with $MgSO_4$ increased the plasma magnesium (Mg) level linearly (p<0.05) and had a trend to increase total protein level (p>0.05 and p<0.10). However, an increase in the dietary $MgSO_4$ level resulted in a linear decrease in the colostrum fat content (p<0.05). Dietary $MgSO_4$ supplementation enhanced the immunoglobulin G (IgG) level (linear, p<0.05) in plasma on day of farrowing and immunoglobulin A (IgA) level in colostrum (quadratic, p<0.05) and milk (linear, p<0.05) of the sows. These results indicated that supplementation with $MgSO_4$ during late gestation and lactation may have the potential to prevent sow constipation, but may also result in some negative effects.

• Restorative Dentistry and Endodontics
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• v.27 no.5
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• pp.488-492
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• 2002

The purpose of this study was to evaluate the effectiveness of plasma arc curing (PAC) unit for composite and compomer curing. To compare its effectiveness with conventional quartz tungsten halogen (QTH) light curing unit, the polymerization shrinkage rates and amounts of three composites (Z100, Z250, Synergy Duo Shade) and one compomer, that had been light cured by PAC unit or QTH unit, was compared using a custome made linometer. The measurement of polymerization shrinkage was peformed after polymerization with either QTH unit or PAC unit. In case of curing with the PAC unit, the composite was light cured with Apollo 95E for 6s, the power density of which was recorded as 1350 mW/$\textrm{cm}^2$ by Coltolux Light Meter. For light curing with QTH unit, the composite was light cured for 30s with the XL2500, the power density of which was recorded as 800 mW/$\textrm{cm}^2$ by Coltolux Light Meter. The amount of linear polymerization shrinkage was recorded in the computer every 0.5s for 60s. Ten measurements were made for each material. The amount of linear polymerization shrinkage for each material in 10s and 60s which were cured with PAC or QTH unit were compared with t test. The amount of polymerization shrinkage in the tested materials were compared with 1way ANOVA with Duncan's multiple range test. As for the amounts of polymerization shrinkage in 60s, there was no difference between PAC unit and QTH unit in Z250 and Synergy Duo Shade. In Z100 and Dyract AP, it was lower when it was cured with PAC unit than when it was cured with QTH unit (p<0.05). As for the amounts of polymerization shrinkage in 10s, there was no difference between PAC unit and QTH unit in Z100 and Dyract AP. The amounts of polymerization shrinkage was significantly higher when it was cured with PAC unit in Z250 and Synergy Duo Shade (p<0.05). The amounts of polymerization shrinkage in the tested materials when they were cured with QTH unit were Z250 (6.6um) < Z100 (9.3um), Dyract AP (9.7um) < Synergy Duo Shade (11.2um) (p<0.05). The amount of polymerization shrinkage when the materials were cured with PAC unit were Dyract AP (5.6um) < Z100 (8.1um), Z250(7.0um) < Synergy Duo Shade (11.2um) (p<0.05).

• Korean Journal of Veterinary Research
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• v.27 no.2
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• pp.339-345
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• 1987

Each of twenty blood samples taken from apparently healthy Korean Cows was used to produce five different mixtures of autologous plasma and blood corpuscles such that their values of packed cell volume (PCV) lay between 10 to 50ml/l00ml. The measurements of erythrocyte sedimentation rate (ESR) using 45 degree-angled capillary hematocrit tube, 1.1-1.2mm bore, ($45^{\circ}-micro-ESR$) were practised for the blood of various levels of PCV under the ambient temperature of ${10^{\circ}C}$, ${20^{\circ}C}$ and ${30^{\circ}C}$. Correlation of ESR to ambient temperature showed linear regression each in five levels of PCV. ESR increased with ascending ambient temperature, and magnitude of the increase of ESR became greater as the level of PCV lowered. Correlation of ESR, of which values were transformed by the linear regression equation correlated to ambient temperature to PCV showed curvilinear regression each in three levels of ambient temperature, and ESR was increased with decreasing PCV. The data were statistically analysed and a list of relative anticipate $45^{\circ}-micro-ESR$ values for PCV and ambient temperature was presented.

• Journal of The Korean Astronomical Society
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• v.33 no.1
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• pp.47-55
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• 2000

Nonpotential characteristics of magnetic fields in AR 5747 are examined using Mees Solar Observatory magnetograms taken on Oct. 20, 1989 to Oct. 22, 1989. The active region showed such violent flaring activities during the observational span that strong X-ray flares took place including a 2B/X3 flare. The magnetogram data were obtained by the Haleakala Stokes Polarimeter which provides simultaneous Stokes profiles of the Fe I doublet 6301.5 and 6302.5. A nonlinear least square method was adopted to derive the magnetic field vectors from the observed Stokes profiles and a multi-step ambiguity solution method was employed to resolve the $180^{\circ}$ ambiguity. From the ambiguity-resolved vector magnetograms, we have derived a set of physical quantities characterizing the field configuration, which are magnetic flux, vertical current density, magnetic shear angle, angular shear, magnetic free energy density, a measure of magnetic field discontinuity MAD and linear force-free coefficient. Our results show that (1) magnetic nonpotentiality is concentrated near the inversion line in the flaring sites, (2) all the physical parameters decreased with time, which may imply that the active region was in a relaxation stage of its evolution, (3) 2-D MAD has similar patterns with other nonpotential parameters, demonstrating that it can be utilized as an useful parameter of flare producing active region, and (4) the linear force-free coefficient could be a evolutionary indicator with a merit as a global nonpotential parameter.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.1
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• pp.149-156
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• 2017

Graphene nanoplatelet (GNP)-reinforced alumina ($Al_2O_3$) is a promising material for micro-partapplications, particularly micro-nozzle shapes, because of its excellent wearresistance. In this study, a $Al_2O_3$/GNPcomposite with 15 vol% graphene nanoplatelets (GNP) was highly densified and fabricated via spark plasma sintering for micro-electrical discharge drilling (Micro-ED drilling) and the wear resistance property of the composite is evaluated via the ball-on-disk method. In addition, the diameter and shape of the micro-electrodes machined by wire electrical discharge grinding (WEDG), block electrical discharge grinding (BEDG), and new linear block moving electrical discharge grinding (LBMEDG) methods are systematically compared and analyzed to observe the micro-hole machining in the micro-ED drilling of the $Al_2O_3$/15vol% GNP composite.

• Journal of Power Electronics
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• v.7 no.1
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• pp.38-43
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• 2007

An External Electrode Fluorescent Lamp (EEFL) has longer lifespan, higher power efficiency and higher luminance than a Cold Cathode Fluorescent Lamp (CCFL). Moreover, it is easy to drive them in parallel. Therefore, the EEFL is expected to quickly replace the CCFL in LCD backlight systems. However, the EEFL has more complex characteristics than the CCFL with a resistive component, because it has both a resistive component by plasma and a capacitive component by external electrode. In this paper, values of resistance and capacitance are measured at several power levels and at several operating frequencies. They are expressed by a numeral formula based on a linear approximation that represents the equivalent resistance and capacitance as a function of power. Then we made block diagram of the equivalent circuit model using numerical expressions. Simulation waveforms and experimental results are presented to verify the feasibility of the equivalent model.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.92.2-92.2
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• 2011

In view of the planned NASA's and ESA's Solar Probe Plus and Solar Orbiter missions, respectively, to probe the inner heliosphere and the Sun's corona, it is timely to investigate outstanding problems associated with the solar wind. Among them is the temperature anisotropy problem. As the solar wind expands into the interplanetary space, the density and magnetic field decreases radially, thus leading to temperature anisotropy ($T_{\parallel}{\gg}T_{\perp}$). However, the measured temperature anisotropy can at times be characterized by $T_{\perp}$ > $T_{\parallel}$, while at other times the measured $T_{\parallel}/T_{\perp}$ is much milder than predicted by adiabatic theory. Physical reasons remain poorly understood. This notwithstanding, it is known from plasma physics that for $T_{\perp}$ > $T_{\parallel}$ electromagnetic ion-cyclotron (EMIC) and mirror instabilities are excited, while for $T_{\parallel}$ > $T_{\perp}$, fire-hose instability is excited. By constructing the threshold conditions for various instabilities, one may construct a closure relation that may be useful for modeling the solar wind. In the present paper we discuss theoretical construction of the anisotropy-beta relation by means of quasi-linear theories of these instabilities. The present work complements previous efforts on the basis of linear theory, hybrid simulations, and empirical fits of observations.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.119.1-119.1
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• 2012

It is well known that the FLRs are excited by compressional waves via mode conversion, but there has been no apparent criterion on the maximum amplitude in the regime of linear approximations. Such limited range of amplitude should be understood by including nonlinear saturation of FLRs, which has not been examined until now. In this study, using a three-dimensional magnetohydrodynamic (MHD) simulation code, we examine the evolution of nonlinear field line resonances (FLRs) in the cold plasmas. The MHD code used in this study allows a full nonlinear description and enables us to study the maximum amplitude of FLRs. When the disturbance is sufficiently small, it is shown that linear properties of MHD wave coupling are well reproduced. In order to examine a nonlinear excitation of FLRs, it is shown how these FLRs become saturated as the initial magnitude of disturbances is assumed to increase. Our results suggest that the maximum amplitude of FLRs become saturated at the level of the same order of dB/B as in observations roughly satisfies the order of ~0.01. In addition, we extended this study for the plasma sheet boundary layer (PSBL) region. We can discuss the maximum disturbances of the Alfven via mode conversion becomes differently saturated through each region.