• Journal of Powder Materials
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• v.8 no.2
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• pp.124-130
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• 2001

A centrifugally atomized 2024A1/SiC/sub p/ composites were extruded to study effect of clusters on mechanical properties, and a model was proposed that the strength of MMCs would be estimated from the load transfer model approach that taken into consideration of the clusters. This model has been successfully utilized to predict the strength and fracture toughness of MMCs. The experimental and calculated results show coincidence and that the fracture toughness decreases with increasing the volume fraction of particles. On the basis of experimental observations, we suggest that the strength and fracture toughness of particle reinforced MMCs may be calculated from; σ/sub y/=σ/sub m/V/sub m/+σ/sub r/(V/sub r/-V/sub c)-σ/sub r/V/sub c/, K/sub IQ/=σ/sub Y/((3πt)((r/sub r//V/sub r/)(r/sub c//V/sub c/))/sup 1/2/)/sup 1/2/, respectively.

• The Korean Journal of Physiology
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• v.5 no.2
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• pp.41-44
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• 1971

Thiocyanate space was determined in 23 bilaterally nephrectomized rabbits in acute metabolic acidosis and alkalosis. Acid-base disturbances were induced by the infusion of 0.3 N HCI or 0.3 N NaOH solution intravenously with the rate of 1 ml/min for 40 to 60 minutes. The blood pressure was monitored throughout the experiment and no changes in blood pressure was confirmed. The following results were obtained. 1. In the saline infused control rabbits, PH was 7.385 with negligible change in pH after the infusion, SCN space was 23.6% of body weight. 2. In the metabolic acidosis group, pH dropped from 7.417 to 7 130 and SCN space was 22.8% of body weight and suggested a negligible change in the extracellular space volume. 3. In the metabolic alkalosis group, pH increased from 7.393 to 7.478 and SCN space was 25.7% of body weight which confirmed a significant increase in the extracellular space volume.

• Journal of Plant Biotechnology
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• v.6 no.2
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• pp.125-130
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• 2004

Callus and cell suspension cultures of Eurycoma longifolia Jack could be an alternative supply of 9-hydroxycanthin-6-one and 9-methoxycanthin-6-one. The callus tissues were initiated from leaves of different trees. The friable calli were used for the preparation of the cell suspension cultures of E. longifolia. The leaf explant of tree Eu-9 produced the most callus and also induced high cell biomass in the cell suspension culture, but it produced low quantity of 9-methoxycanthin- 6-one and 9-hydroxycanthin-6-one. The leaf explant from tree Eu-8 produced low quantity of callus and cell biomass, but produced the highest quantity of 9-methoxycanthin- 6-one and 9-hydroxycanthin-6-one. Optimum production of cell biomass was obtained on cell culture medium with pH 5.75 prior to autoclaving, but high alkaloids content could be induced in culture medium in acidic condition with pH 4.75 and 5.25 prior to autoclaving.

• Journal of Korea Foundry Society
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• v.18 no.4
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• pp.373-382
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• 1998

Particulate reinforced aluminum alloys produced by indirect squeeze casting are difficult to shape by cutting or milling. Therefore near net shape forming of complex shapes is of high economic and technical interest. The complex shape products of $SiC_p/6061$ Al composites are fabricated by the melt-stirring and indirect squeeze casting process. The mold temperatures are $200^{\circ}C$ and $300^{\circ}C$ and applied pressures are 70, 100, and 130 MPa. The volume fractions of the reinforcements are in the range of 5 vol% to 15 vol%. The reinforcement dispersion state are observed using on optical microscope. By employing observed results systematically a correlation is demonstrated among the microstructure, particles behavior, mechanical properties and processing parameters for an optimum melt-stirring(compocasting) and indirect squeeze casting process of MMCs. A procedure to establish the optimum squeeze casting of Al-MMCs is proposed.

• Journal of Nutrition and Health
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• v.27 no.6
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• pp.591-598
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• 1994

The longitudinal changes in transitional milk intakes and body weight of infants(18 boys, 10 girls) have been studied in the part of Kangwon Province from 7 days to 15 days postpartum. Milk intakes at 7, 10, 15 days postpartum were 474$\pm$155, 524$\pm$154 and 547$\pm$130g, respectively. The mean milk intakes were 515g from 7 to 15 days postpartum. Milk intakes of boys were significantly higher than those of girls. The transitional milk intakes per weight of infants appeared 147$\pm$41g/kg. The number of feed per day of boys were significantly higher than those of girls. Milk intakes per fed were 56$\pm$20g. The transitional milk intakes were affected by gestational period(p<0.05), maternal height(p<0.05) and mother's transitional milk yields (p<0.001). Infants transitional milk intakes were 82.6$\pm$17.0% of mothers transitional milk yields. Infants gained its weight 24.6, 40.1 and 39.0g/day at, 7, 10, 15 days postpartum, respectively.

• Proceeding of EDISON Challenge
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• 2017.03a
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• pp.708-711
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• 2017

전기적 신호의 이상으로 발생하는 심방 부정맥은 심방세동으로 발전하는 대표적 심장 질환이다. 이러한 원인에는 세포 내 이온 채널의 유전적 결함으로 인한 기전이 알려져 있다. 지속적인 연구로 밝혀진 대표적인 유전적 질환 중 하나로서 KCNH2 유전자 돌연변이가 있다. 본 연구에서는 KCNH2 유전자 돌연변이가 심방부정맥을 유발하는 연관성연구를 기반으로 심실에서의 심장 질환 발현 연관성을 확인하고 심실부정맥과 심실세동 가능성을 예측하였다. 이를 위해 Ten tusscher 세포 모델에 KCNH2 유전자의 N588K, L532P 변이를 적용하여 2차원과 3차원 시뮬레이션을 진행하였다. wild-type(WT)과 mutant-type(MT)의 전기전도 패턴을 비교했다. 그 결과 WT의 전도파형이 일찍 자가소멸(self-termination) 되는 것과 대조적으로 MT는 회귀성 파형이 유지되었다(WT : 3.6초간 유지, MT : 지속적). 따라서 본 연구를 통해 KCNH2 유전자 돌연변이가 심실 조직의 취약성 (Action Potential Duration 감소, WT : 270 ms, N588K : 130 ms, L532P : 100 ms)을 증가시켜 부정맥의 요인이 됨을 확인하였다.

• Journal of electromagnetic engineering and science
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• v.7 no.2
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• pp.64-68
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• 2007

An InGaP/GaAs HBT based differential Colpitts voltage control oscillator(VCO) is presented in this paper. In the VCO core, two switching transistors are introduced to steer the core bias current to save power. An LC tank with an inductor quality factor(Q) of 11.4 is used to generate oscillation frequency. It has a superior phase noise characteristics of -130.12 dBc/Hz and -105.3 at 1 MHz and 100 kHz frequency offsets respectively from the carrier frequency(1.566 GHz) when supplied with a control voltage of 0 volt. It dissipates output power of -5.3 dBm. Two pairs of on-chip base collector (BC) diodes are used in the tank circuit to increase the VCO tuning range(168 MHz). This VCO occupies the area of $1.070{\times}0.90mm^2$ including buffer and pads.

• Food Science and Preservation
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• v.4 no.2
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• pp.123-130
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• 1997

To develop the prediction program for quality change of Citrus unshiu during marketing, we examined the quality characteristics of Citrus unshiu stored at experimental refrigerator set to 4, 8, 12 and 16$^{\circ}C$ for 2 months. According to the storage temperature the changes of quality characteristics were different respectively, but it was most severe during 16$^{\circ}C$ storage. Activation energy and Q10 value were 6683.16 cal/mol K and 1.53 respectively. The determination coefficient of regression equation of pH, acidity and vitamin C by surface response analysis were over 0.85. Using these regression equation, we developed the prediction program for the change of pH, acidity and vitamin C contents. The calculated values and experimental values of pH, acidity and vitamin C contents for short-term storage of Citrus unshiu were coincided well.

• Korean Journal of Microbiology
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• v.25 no.1
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• pp.1-8
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• 1987

An extracellular $\beta$-1, 3-glucanase from Pseudomonas stutzeri KF 13 was purified about 390 with 26% recovery. The purified enzyme revealed a single band by polyacrylamide gel electrophoresis and SDS-polyacrylamide gel electrophoresis. The enzyme was stable in a pH 6.0 to 9.0, and relatively thermostable. The optimal pH and temperature on the enzyme activity were found to be 5.8 and 45.deg.C, respectively. The activation energy was calculated to be 16,130 cal per mole. The Km value for laminarin was found to be 3ng per ml and the molecular weight was determined to be 28,000 by gel filtration and 26,000 daltons by SDS-acrylamide gel electrophoresis. The enzyme was inhibited by 1.0mM of $Hg^{2+}$, and strongly inhibited by 1.0mM of p-chloromercuribenzoic acid.

• Korean Journal of Psychosomatic Medicine
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• v.23 no.2
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• pp.79-85
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• 2015

Objectives : To investigate clinical and symptomatic differences among motoric subtypes of delirium. Methods : A total of 256 patients referred to psychiatric consultation services for delirium due to general medical condition were assessed retrospectively. Motoric subtypes were determined according to Lipowski's criteria for hyperactive, hypoactive and mixed subtypes. All patients were evaluated according to Delirium Rating Scale-Revised-98(DRS-98-R) by trained psychiatrists to obtain symptomatic profiles of delirium. Results : Hyperactive subtype were 50.8%(n=130), mixed 46.1%(n=118) and hypoactive 3.1%(n=8). Hyperactive patients were younger than mixed subtype($69.62{\pm}13.976$ vs. $73.97{\pm}11.569$, p=0.022) and received antipsychotics to manage symptoms of delirium more frequently(83.8% vs. 57.6%, p<0.001). Hyperactive patients had higher DRS-R-98 scores on both noncognitive($7.14{\pm}3.543$ for hyperactive, $5.62{\pm}3.279$ for mixed subtype) and cognitive subscales($10.00{\pm}3.574$ for hyperactive, $6.38{\pm}2.875$ for hypoactive, $7.43{\pm}3.771$ for mixed subtype, p<0.001). Conclusions : We demonstrated that clinical and symptomatic profiles were different across motoric subtypes in delirium. Diagnostic and therapeutic approach should be made differently according to motoric subtypes of delirium and special attention is needed not to underestimate or delay treatment in specific motoric subtype of delirium.