• Korean Journal of Agricultural Science
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• v.48 no.4
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• pp.965-973
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• 2021

The intention of this research is to analyze the effects of lactulose (LAC) supplementation on the growth performance, nutrient digestibility, microbial shedding, and fecal noxious gas emissions on weaning pigs in a 42-day trial. Based on the initial body weight and sex, a total of 255 piglets (21 day old) were randomly allocated into one of three dietary treatments with 15 replications and five pigs (two female and three male) per pen. The dietary treatments were as follows: a corn-soybean meal-based basal diet (CON) supplemented with 0, 1, and 2 g·kg^-1 of LAC. During phase 1, significant (p < 0.05) increases in the average daily feed intake and average daily gain (ADG) were observed, whereas during phase 2 and overall experimental period, significant improvements (p < 0.05) in the body weight, ADG, and gain to feed ratio were observed in pigs fed a graded level of LAC compared to those fed the CON diet. Additionally, dietary LAC supplementation significantly improved (p < 0.05) the nutrient digestibility dry matter, nitrogen, and gross energy in both phase 1 and phase 2. Moreover, the inclusion of LAC supplementation significantly increased (p < 0.05) the fecal Lactobacillus counts and reduced (p > 0.05) the E. coli counts in pigs. Furthermore, LAC supplementation reduced (p > 0.05) fecal ammonia and hydrogen sulfide gas emissions during phase 2. The results here indicate that the addition of lactulose at 1 g·kg^-1 and/or 2 g·kg^-1 would be optimal to improve the performance outcomes of weaning piglets.

• Journal of Animal Science and Technology
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• v.62 no.2
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• pp.198-207
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• 2020

This experiment was performed to evaluate the optimal proportion of dietary standardized ileal digestible lysine (SID Lys) to net energy (NE) proportion in growing to finishing pigs. A total of seventy-two pigs were used at phase 1 (initial body weight 37.23 ± 0.23 kilogram, for 42 d) and at phase 2 (initial body weight 54.16 ± 0.20 kilogram, for 77 d). They were arbitrarily assigned to three treatments groups consisting of four duplicates per treatment (six pigs in duplicates, respectively). Diet treatments were as follows: CON = basal diets (phase 1, crude protein (CP): 19.1%; SID Lys: 0.94%; SID Lys: NE proportion: 0.91 g/MJ / phase 2, CP: 17.0%; SID Lys: 0.84%; SID Lys: NE proportion: 0.79 g/MJ), TRT1 (phase 1, CP: 18.0%; SID Lys: 0.92%; SID Lys: NE proportion: 0.89 g/MJ / phase 2, CP: 15.8%; SID Lys: 0.8%; SID Lys: NE proportion: 0.75 g/MJ), TRT2 (phase 1, CP: 17.3%; SID Lys: 0.82%; SID Lys: NE proportion: 0.79 g/MJ / phase 2, CP: 14.8%; SID Lys: 0.7%; SID Lys: NE proportion: 0.65 g/MJ). In phase 1 and 2, growth performance did not meaningfully be affected when SID Lys: NE proportion decreased with reducing CP content. In phase 2, the nitrogen digestibility of CON group in 11 week was higher (p < 0.05) than other treatments. Also, marbling and firmness scores of TRT2 group diets increased (p < 0.05) compared with those of CON group, but dissimilarities of other meat qualities did not be detected among treatments. In conclusion, introduction of NE system can reduce negative problems introduced when dietary CP decreased. Also, 0.79 and 0.65 g/MJ of SID Lys: NE proportion is the optimal Lys: NE proportion to achieve improved pork quality without impairing the growth performance in growing-finishing pigs, respectively.

• Journal of Microbiology and Biotechnology
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• v.8 no.5
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• pp.543-546
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• 1998

The effect of glucose concentration on the production of erythritol by Trichosporon sp. was mainly studied. The specific growth rate and production rate of erythritol gave the highest values of $0.23 h^{-1}\; and\; 4.2 g/\ell/h,\; respectively,\; on\; 100 g \; glucose/\ell$ of medium. The conversion yield of erythritol during the exponential phase and the stationary phase was constantly maintained at 19% and 51 %, respectively, while the glucose concentration in the medium varied from 100 g/$\ell$ to 400 g/$\ell$. The maximum overall erythritol conversion yield of 47% was obtained when the glucose concentration in the medium was 400 g/$\ell$. It corresponded to a 74% increase compared with the 100 g/$\ell$ glucose medium. The diauxy growth of this microbe was also observed. It grew exponentially consuming glucose, then after the second lag phase, biomass slowly increased using glycerol and erythritol.

• Journal of Microbiology and Biotechnology
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• v.11 no.6
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• pp.1055-1060
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• 2001

Experimental data for the on-line estimation of cell concentration and growth rate are presented. For this purpose, we utilized the on-line calculation of the oxygen uptake rate (OUR), which was derived from a liquid phase dynamic mass balance for the oxygen during the active growth phase in cyclosporin A (CyA) fermentation. The cell yield coefficient, based on the oxygen $(Y_{x/o})$for both suspended and immobilized cells of Tolypocladium inflatum, was estimated as $1.9 gDCW/gO_2$ from a very good linear correlation between the cell mass produced and the total oxygen consumed. The calculated yield showed a good agreement with the value of $(Y_{x/o})$ generated from the correlation between the cell growth rate and the oxygen uptake rate. In addition, further experimental data are given, which were also applied to determine the specific oxygen uptake rate of T. inflatum cells during the exponential phase of CyA fermentation. A theoretical basis for the analysis of these fermentation parameters is also provided.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.2
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• pp.292-300
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• 1997

PSZT powders having the particle size of 0.5~5 $\mu\textrm{m}$ with cubic shapes, were prepared by a hydrothermal reaction in the temperature range of 150~$^{\190circ}C$ for a 2 h reaction. Experimental results showed that as the reaction temperature increased, the nucleation and crystal growth were accelerated and the the particle size became larger. However, the particle size became smaller with its narrow distribution as the concentration of a mineralizer (KOH) increased. It was possible to reduce the reaction temperature by increasing mineralizer concentrations. With increase in Zr/Ti ratio, the major crystal phase of synthetic PSZT powders was seen to change from tetragonal phase to rhombohedral phase.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1999.06a
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• pp.115-127
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• 1999

The charged clusters or particles, which contain hundreds to thousands of atoms or even more, are suggested to form in the gas phase in the thin film processes such as CVD, thermal evaporation, laser ablation, and flame deposition. All of these processes are also used in the gas phase synthesis of the nanoparticles. Ion-induced or photo-induced nucleation is the main mechanism for the formation of these nanoclusters or nanoparticles inthe gas phase. Charged clusters can make a dense film because of its self-organizing characteristics while neutral ones make a porous skeletal structure because of its Brownian coagulation. The charged cluster model can successfully explain the unusual phenomenon of simultaneous deposition and etching taking place in diamond and silicon CVD processes. It also provides a new interpretation on the selective deposition on a conducting material in the CVDd process. The epitaxial sticking of the charged clusters on the growing surface is gettign difficult as the cluster size increases, resulting in the nanostructure such as cauliflowr or granular structures.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.3
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• pp.289-294
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• 1999

The charged clusters or particles, which contain hundreds to thousands of atoms or even more, are suggested to from in the gas phase in the thin film processes such as CVD, thermal evaporation, laser ablation, and flame deposition. All of these processes are also phase synthesis of the nanoparticels. Ion-induced or photo-induced nucleation is the main mechanism for the formation of these nanoclusters or nanoparticles in the gas phase. Charge clusters can make a dense film because of its self-organizing characteristics while neutral ones make a porous skeletal structure because of its Brownian coagulation. The charged cluster model can successfully explain the unusual phenomenon of simultaneous deposition and etching taking place in diamond and silicon CVD processes. It also provides a new interpretation on the selective deposition on a conducting material in the CVD process. The epitaxial sticking of the charged clusters on the growing surface is getting difficult as the cluster size increases, resulting in the nanostructure such as cauliflower or granular structures.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.3
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• pp.494-503
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• 1997

We investigated the initial stages of formation of the Cu/polyimide interface using another two methods by X-ray photoelectron spectroscopy. : One, in-situ measurement with increasing of Cu deposition thickness onto polyimide(PI), the other, measurement with decreasing of Cu thickness of Cu/pI film by $Ar^+$ ion etching. From these results, we find that the chemical reactions exist in Cu/PI interface. However, the measured chemical reactions were different according to experimental method.

• Journal of Environmental Science International
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• v.15 no.12
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• pp.1177-1183
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• 2006

This study was carried out to evaluate effect of sludge characteristics (pH, SVI, anaerobic storage, wet density and growth phase) on the sedimentation of bulking sludge of paper manufacturing plant. The results showed that mix hulking sludge with sewage sludge (10-60%) caused the decrease of SVI, the settled sludge concentration was increased. Increase of anaerobic storage time (0 to 8 day) was increased SVI, sedimentation performance was deteriorated. The sedimentation was improved by addition of loess (0.2-5.0 g/L), because wet density of sludge was increased and SVI was decreased. At an exponential phase, the ratio of sedimented/growthed sludge concentration was decreased, the ratio was increased after stationary phase.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.541-545
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• 2000

For the sustained release formulation of recombinant human growth hormone (rhGH), dissociable rhGH aggregates were microencapsulated within poly(D,L-lactic-co-glycolic acid) [PLGA] microparticles. rhGH aggregates with 2 - 3 m Particle diameter were first produced by adding a small volume of aqueous rhGH solution into a partially water miscible organic solvent phase(ethyl acetate) containing PLGA. These rhGH aggregates were then microencapsulated within PLGA polymer phase by extracting ethyl acetate into an aqueous phase pre-saturated with ethyl acetate. The resultant microparticles were 2 - 3 m in diameter similar to the size of rhGH aggregates, suggesting that PLGA polymer was coated around the protein aggregates. Release profiles of rhGH from these microparticles were greatly affected by changing the volume of the incubation medium. The release rhGH species consisted of mostly monomeric form with having a correct conformation. This study reveals that sustained rhGH release could be achieved by microencapsulating reversibly dissociable protein aggregates within biodegradable polymers.