• BMB Reports
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• v.38 no.3
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• pp.294-299
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• 2005

In this report, we describe the high-yield secretory expression of the recombinant human anti-HBsAg Fab fragment from Pichia pastoris that was achieved by co-integration of the genes encoding the heavy and light chains (both under the control of alcohol oxidase promoter) into the genome of the yeast cells. The fed-batch fermentations were carried out in a 5 L scale. Both chains of the Fab were successfully expressed upon methanol induction. The absorbance ($OD_{600}$) of the broth can reach 350~500 at the end of fed-batch phase. After the induction, the expression level of the recombinant Fab (soluble) reached 420~458 mg/L. The recombinant Fab fragment was purified from the crude culture supernatant by ion exchange chromatography and the purity of the recombinant Fab fragment was over 95%. The affinity activities of the crude fermentation supernatant and the purified Fab were analyzed by indirect ELISA, which showed that the purified recombinant Fab fragment had high affinity activity with hepatitis B surface antigen.

• The Transactions of the Korean Institute of Power Electronics
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• v.12 no.4
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• pp.310-317
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• 2007

In this paper, the system equation for the balanced two-phase induction motor is derived and the characteristics for speed control is also analyzed in the region of constant torque and constant power. The modified vector control theory is applied to two-phase motor drive system. The speed of two-phase motor drive can be controlled precisely by the modified indirect vector control theory. The modified vector control theory is simpler comparing to the conventional vector control because of the simpler axis transformation. The computer simulations and the experimental results presented to confirm the vector control for two-phase inverter fed two phase induction motor system.

• Journal of Nutrition and Health
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• v.39 no.8
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• pp.733-741
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• 2006

The study was conducted to investigate the effects of dietary calcium and soy isoflavone on body fat and lipid metabolism in high fat-induced obesity. Four week old female C57/BL6J mice, known as a good model of diet-induced obesity, were fed low Ca and high fat diet for 6 weeks. After induced obesity, mice were divided into six groups according to diets varying calcium contents (0.1 or 1.5%) and genistein contents (0 or 500 or 1,000 ppm). Body weight, fat pad (perirenal fat and parameterial fat), adipocyte size, serum total lipid and total cholesterol were significantly decreased by both high Ca intake and genistein supplementation. However, the effect of genistein supplementation showed in low Ca-fed groups. Serum LDL-cholesterol and TG were significantly decreased by high Ca intake and genistein supplementation, respectively. In liver, lipogenic enzymes (fatty acid synthase and malic enzyme) activity and TG were significantly decreased by both high Ca intake and genistein supplementation. This inhibitory effect of genistein on lipogenic enzymes showed in low Ca-fed groups. But liver total cholesterol and total lipid were significantly decreased by high Ca intake and genistein supplementation, respectively. Fecal excretion of total lipid, total cholesterol and TG were significantly increased by high Ca intake, not by genistein supplementation. In conclusion, high calcium intake and genistein supplement may be beneficial for suppression of obesity through direct anti-adipogenesis by decreasing fat weight and size and indirect anti-lipo-genesis by inhibiting lipogenic enzymes activity and improving lipid profile.

• Journal of The Korean Society of Grassland and Forage Science
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• v.34 no.4
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• pp.283-287
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• 2014

This experiment was conducted to determine methane production and emission factors for a range of roughage diets fed to Hanwoo cows at a level of maintenance energy requirement. Seven cows were fed mixed hay only, 12 cows were fed mixed hay containing 30~50% rice straw and 6 cows were fed a mixed hay diet supplemented with 1.0 kg of wheat bran. Each cow was placed in a metabolic crate for 10 consecutive days, including last 7 days for sampling of feces and urine. At the end of the sampling period, the cows were transferred to an open-circuit respiration chamber for 24 consecutive hours. Methane conversion rate (5.5~6.2%, mean value = 5.8%) and emission factor (33.6~38.6 kg/head/year, mean value = 35.2) were not significantly affected by the diets although the mixed hay only diet resulted in 11 and 15% higher respective rates than the other two. However, in light of the many assumptions that forage with good quality might reduce methane production, additional experiments should be required for participation in the greenhouse gas emission trading system.

• Proceedings of the IEEK Conference
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• 2003.07c
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• pp.2943-2946
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• 2003

In this paper are described the indirect induction healed boiler and induction boated hot air producer using the voltage-fed series resonant high-frequency inverter which can operate in the frequency range from 20［kHz］to 50［kHz］. A specially designed induction heater, which is composed of laminated stainless assembly with many tiny holes and interconnected spot welding points between stainless plates, is inserted into the ceramic type vessel with external working coil. This working coil is connected to the inverter and turbulence fluid through this induction heater to moving fluid generates in the vessel. The operating performances of this unique appliance in next generation and its effectiveness are evaluated and discussed from a practical point of view.

• Proceedings of the KIPE Conference
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• 2003.07a
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• pp.19-22
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• 2003

In this paper are described the indirect induction heated boiler and induction heated hot air producer using the voltage-fed series resonant high-frequency inverter which can operate in the frequency range from 20 [kHz] to 50 [kHz]. A specially designed induction heater, which is composed of laminated stainless assembly with many tiny holes and interconnected spot welding points between stainless plates, is inserted into the ceramic type vessel with external working coil. This working coil is connected to the inverter and turbulence fluid through this induction heater to moving fluid generates in the vessel. The operating performances of this unique appliance in next generation and its effectiveness are evaluated and discussed from a practical point of view.

• Proceedings of the KIEE Conference
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• 1988.11a
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• pp.306-309
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• 1988

For the purpose of fast response and simplifing system angle control strategy is selected. And the analysis and dynamic performance of a slip frequency controlled current source inverter fed induction motor drive with stator frequency compensation (indirect torque angle control) is investigated. The current control loop including motor is modeled and speed control loop including the frequency compensation is analysed. And transfer function of overal system is simplified. Experimental results are given in support of the analytical procedure.

• Journal of Mechanical Science and Technology
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• v.16 no.5
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• pp.633-638
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• 2002

An approach to enhance dimensional accuracy of the grinding process has been presented, and grinding of a glass material with a metal-bonded diamond wheel has been studied. In this study, a grinding tool is suspended flexibly and controlled by an electromagnetic actuator. During grinding, profile error of a ground surface is indirectly measured and fed back to a control system. A model of grinding error has been suggested on which the indirect measurement has been based. An optimal PID control is adopted and effectiveness of the in-process feedback control has been verified experimentally.

• Nutritional Sciences
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• v.9 no.1
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• pp.20-28
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• 2006

Aryl sulfotransferase (AST) IV is a liver enzyme involved in detoxication and has been shown to be susceptible to down regulation by a number of hepatotoxic xenobiotics. Studies presented here to investigate the ability of biological and non-biological divalent metal cations on AST IV activity showed that AST IV was strongly inhibited following in vitro or in vivo exposure to. Zn ( II ), Co ( II ) or Cd ( II ). It was found that $0.025\sim$2.5 uM of these metal ions were sufficient to cause $50\%$ of inhibition in vitro in purified AST IV and $0.25\sim$25 uM of these metal ions in liver cytosolic fractions. For the in vivo study, 1,000 mg Cu ( II )/kg, 2,000 mg Zn ( II )/kg or 250 mg Cd( II )/kg was added to individual diets and administered to three (3) group; of mts over a 7 week period The Co ( II )-supplemented diet produced no apparent change in rat growth rate and resulted in 30-fold increase in liver cytotolic Cu ( II ) levels, suggesting that elevated levels of Cu ( II ) ion in the liver were responsible for the loss of AST IV activity. In contrast, the Zn ( II )-supplemented diet caused a decrease in rat growth rates and resulted in zero increase in liver Zn ( II ) levels, which suggested an indirect inhibition mechanism was caused by Zn ( II ) in the liver. Rats were fed the Cd-supplemented diet also displayed a decrease in growth rate with little or no change in liver Cu ( II ) or Zn ( II ) levels. When the liver cytosols of mts from the metal ion diets were immunochemically analyzed for the AST IV and albumin contents, no significant changes were observed in albumin levels. However, AST IV contents in the cytosols of mts fed the Zn ( II )-supplemented diets showed a slight decrease in amount These results showed that AST IV activity in vitro and in vivo can be inhibited by Co ( II ), Zn ( II ), and Cd ( II ) by apparently different mechanisms. The immediate response to a Zn injection showed a decrease in AST IV activity but not in the AST IV content in liver cytosol. These mechanisms appeared to involve direct actions of the metal ion on AST IV activity and indirect actions affecting AST IV amount.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.2
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• pp.198-205
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• 2011

This study was conducted to investigate the effect of feed types on Ochratoxin A (OTA) degradation by Korean native goats. Rumen fluid from canulated goats fed whole roughage or 50% roughage served as a source of micro-organisms. Experiments were undertaken i) to investigate OTA degradation ability in a $2{\times}4$ factorial arrangement with different feed types (100% roughage vs. 50% roughage) and rumen fluid fractions (whole rumen fluid, cells, autoclaved rumen fluid and supernatant) supplemented with OTA ii) to evaluate OTA degradation by the rumen fluid of goats fed two different diets at different time points (0, 3, 6, 9 and 12 h) of feeding iii) to isolate potential rumen microorganisms and iv) to identify elements responsible for OTA degradation. Rumen fluid from goats fed 100% roughage had higher (p<0.05) OTA degradability than 50% roughage diets. OTA degradation based on rumen fluid collection times showed that rumen fluid at 0 h showed significantly higher (p<0.05) degradability. Carboxypeptidase A (CPA) enzyme has been reported to be responsible for OTA degradation. Thus, using real time PCR, primers designed to target the CPA gene from Bacillus licheniformis could be amplified using genomic DNA from rumen fluid of goats and sequenced, thus enabling evaluation of the Bacillus population under different feeding condition and times. Our findings showed that the Bacillus population was significantly higher (p<0.05) before feeding (0 h) in animals which were fed a whole roughage diet, giving indirect evidence of OTA degradation being influenced by Bacillus sps. Thus, it can be concluded that OTA degradability is influenced by feed, feeding time and Bacillus licheniformis population.