• Journal of Korea Port Economic Association
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• v.28 no.1
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• pp.179-201
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• 2012

Since 1993, M&A activities have been frequent in Liner shipping market. This study examines the effect of M&A on stock price reaction for acquiring firms listed on the market. The study covers the period from 1993 to 2009 and uses 61 daily closing prices of the acquiring firms before and after the M&A announcement day and is analyzed through the market-adjusted model in an event study. After calculating short-term performance using abnormal returns(AR) and cumulative average abnormal returns(CAR) before and after 30 days from the day of event, the results on the test show that the firm's values slightly increased through the M&A, but it does not attest to the statistical significance. In addition, this study investigates the AR difference between estimating windows and post-event windows for the 3 cases of each period before and after 30 days, 15 days, and 7 days from the event day to analyse the impact of M&A on the addition of acquiring firm's value. Our findings suggest that the M&A between Liner shipping companies is targeted for the long-term business strategy instead of the instant rise in the value of the firm involved.

• Clean Technology
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• v.8 no.4
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• pp.199-203
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• 2002

To investigate the optimal conditions for biodegradation of toluene by Pseudomonas fluorescens KCTC 1767 in a batch soil-bioreactor, the effects of rpm change from 60 to 180, and temperature change from $15^{\circ}C$ to $30^{\circ}C$ in a batch culture and the flow rate change from 55 mL/min to 85 mL/Min in soil-bioreactor on the biodegradation of toluene were studied. In a batch culture the optimal operating conditons were 60 rpm, and $30^{\circ}C$ at initial pH 7, In a soil-bioreactor the optimal flow rate was 55 mL/min in the flow rate of circulation. The lower flow rate of circulation may help to biodegrade toluene adsorped in soil and dissolved in underground water.

• Journal of Korean Society for Geospatial Information Science
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• v.10 no.4 s.22
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• pp.61-67
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• 2002

This study is aimed to suggest a practical use of GPS continuous stations by conducting the precision analysis using its data. Currently dozens of continuous stations have been installed and operated since the first GPS continuous station built by KAO(Korea Astronomy Observation) in 1985. The utilization of the surveyed information, however, has been under-developed regardless of a significant investment, which leads the necessity of utilization plan. The results of this study show that the mis-closures between the two points at University of Incheon and Suwon/Seoul stations of NGI(National Geography Institute), Seoul stat ion of KAO, and Incheon station of MOGAHA(Ministry Of Government Administration and Home Affairs) are 0.0206m, 0.0118m, 0.0129m and 0.0024m respectively. It indicates that the analyzed mis-closures were less than the allowed values ill the primary/secondary control point specification for GPS surveying, i.e. a mis-closure less than 30mm for the distance less than 30km and a mis-closure less than $IPPM{\times}D(km)$ for the distance greater than 30km.

• Korean Journal of Poultry Science
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• v.30 no.2
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• pp.95-99
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• 2003

A total of 112 male and 1208 female Ross broiler breeders (30-wk-old) were used in this study to investigate whether a male to female (M/F) ratio of broiler breeder chickens may influence fertility and hatchability of hatching eggs. There were three treatments, each consisting of four pens with a size of 3.2 m ${\times}$ 6.4 m. Each pen housed approx. 100 females and 10 males to give the M/F ratio as follows: T1, 1/9; T2, 1/11; and T3, 1/13, respectively. The fertility of broiler breeder eggs ranged between 93 to 94％ at 30 wk of age. At 35 wk of age, breeder eggs from T3 tended to be less fertile (P>0.05) than those from T1 and T2. The low fertility observed in T3 at 35 wk of age further reduced to reach a statistical significance at 46 wk of age (P<0.05) when compared to those of T1 and T2. Hatchability of breeder eggs among treatments tended to follow a similar trend as shown in fertility, keeping hatchability of breeder eggs from T3 low when compared to the groups of T1 and T2. Our results indicated that the M/F ratio influenced fertility and consequently hatchability of breeder eggs. Furthermore, our study suggests that either 1/9 or 1/11 M/F ratio, but not 1/13 M/F ratio, seems suitable to sustain reproductive performance of broiler breeders throughout the laying periods.

• Structural Engineering and Mechanics
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• v.30 no.1
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• pp.131-133
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• 2008

• Nuclear Medicine and Molecular Imaging
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• v.40 no.3
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• pp.177-185
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• 2006

Purpose: Purpose of this study is to synthesize $^{99m}Tc$-labeled transferrin for injection imaging and to compare it with $^{67}Ga$-titrate for the detection of infectious foci. Materials and methods: Succinimidyl 6-hydrazino-nicotinate hydrochloride-chitosan-transferrin (Transferrin) was synthesized and radiolabeled with $^{99m}Tc$. Labeling efficiencies of $^{99m}Tc$-Transferrin were determined at 10 min, 30 min, 1 hr, 2 hr, 4 hr and 8 hr. Biodistribution and imaging studies with $^{99m}Tc$-Transferrin and $^{67}Ga$-citrate were performed in a rat abscess model induced with approximately $2{\times}10^8$ colony forming unit of Staphylococcus aureus ATCC 25923. Results: Successful synthesis of Transferrin was confirmed by mass spectrometry. Labeling efficiency of $^{99m}Tc$-Transferrin was $96.2{\pm}0.7%,\;96.4{\pm}0.5%,\;96.6{\pm}1.0%,\;96.9{\pm}0.5%,\;97.0{\pm}0.7%\;and\;95.5{\pm}0.7%$ at 10 min, 30 min, 1 hr, 2 hr, 4 hr and 8 hr, respectively. The injected dose per tissue gram of $^{99m}Tc$-Transferrin was $0.18{\pm}0.01\;and\;0.18{\pm}0.01$ in the lesion and $0.05{\pm}0.01\;and\;0.04{\pm}0.01$ in the normal muscle, and lesion-to-normal muscle uptake ratio was $3.7{\pm}0.6\;and\;4.7{\pm}0.4$ at 30 min and 3 hr, respectively. On image, lesion-to-background ratio of $^{99m}Tc$-Transferrin was $2.18{\pm}0.03,\;2.56{\pm}0.11,\;3.08{\pm}0.18,\;3.77{\pm}0.17,\;4.70{\pm}0.45\;and\;5.59{\pm}0.40$ at 10 min, 30 min, 1 hr, 2 hr, 4 hr and 10 hr and those of $^{67}Ga$-citrate was $3.06{\pm}0.84,\;4.12{\pm}0.54\;and\;4.55{\pm}0.74 $ at 2 hr, 24 hr and 48 hr, respectively. Conclusion: Transferrin is successfully labeled with $^{99m}Tc$, and its labeling efficiency was higher than 95% and stable for 8 hours. $^{99m}Tc$-Transferrin scintigraphy showed higher image quality in shorter time compared to $^{67}Ga$-citrate image. $^{99m}Tc$-transferrin is supposed to be useful in the detection of the infectious foci.

• Food Science of Animal Resources
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• v.40 no.2
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• pp.254-261
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• 2020

The aim of this study was to evaluate quality characteristics of pork myofibrillar protein (MP) added with cornstarch as affected by different pH values and salt cocnentrations. MP mixtures were prepared with three different pH values (pH 6.00, 6.25, and 6.50) and three different salt concentrations (0.15, 0.30, and 0.45 M). Cooking yield (CY), gel strength, viscosity, and scanning electron microscopy were measured to evaluate characteristics of MPs. CYs of MPs with cornstarch at above pH 6.25 or salt 0.30 M were increased compared to those at pH 6.00 or salt 0.15 M. However, gel strengths of MPs at salt 0.45 M were higher than those at salt 0.30 M. In microstructure analysis, MP gels with increasing pH value and salt concentration showed compact and uniform structure. Thus, MP gels with pH 6.25 and salt concentration of 0.30 M would be better for manufacturing meat products containing cornstarch to increase their water holding ability.

• Korean Journal of Microbiology
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• v.33 no.3
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• pp.187-192
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• 1997

The strain producing biosurfactant was isolated from soil. The isolated strain was identified as the genus Tsukamurella through its morphological, cultural, physiological, menaquinone type, fatty acid composition characteristics. The highest biosurfactant production by Tsukamurella sp. 26A was observed after 4 days cultivation in the culture medium containing n-hexadecane 7%, $NaNO_{3}$ 0.2%, $K_2HPO_4$ 0.001%, $MgSO_{4}$ center dot $7H_{2}O$ 0.02%, $CaCl_2$ center dot $2H_{2}O$ 0.02%, yeast extract 0.02%(pH 6.8-7.0, 30^{\circ}C.$ The surface and interfacial tension of an aqueous solution reached 30 mNim and 1.5 mNim, respectively. The biosurfactant stabilized oil-in-water emulsion with a variety of hydrocarbons, edible oils and petroleum oils.

• Journal of Nutrition and Health
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• v.24 no.5
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• pp.431-441
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• 1991

To investigate the influence of age and dietary fat level on the immune function and the growing potential of the fibroblast cells, male rats of 2 month, 6 month and 30 month of age were fed either 6% or 30% fat diet for 16 weeks. The weight of thymus decreased linearly with increasing age. And this age-dependent degeneration of thymus was delayed in rats fed low fat diets. The blastogenesis of spleen lymphocytes to PHA, ConA, and PWM was decreased with increasing age, however, no effect of dietary fat level was observed. The age-related decline in ratios of PHA/ConA response may suggest that T suppressor cell activity increases with age. In cell culture system, lung fibroblast cells from 30M rats showed lower plating efficiency. longer doubling time. and shorter cumulative doubling potential than those from 2M or 6M animals. Also. the morphology of fibroblasts from 30M rats was tended to be rouned rather than flattened and more variable in size and being generally larger. wherease those from 2M and 6M rats were uniform in size and adhered tightly to the culture vessel in ordered arrays. Therefore fibroblast cell culture system tried in this study reflects the changes of cellular aging.

• The Journal of Natural Sciences
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• v.17 no.1
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• pp.103-111
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• 2006

Regulation of invertase biosynthesis was studied with the E. coil harboring recombinant plasmid, pYC17. Biosynthesis of invertase in the recombinant E. coil was effectively induced in the presence of 30mM of sucrose for 3h. Glucose also repressed the invertase induction in the recombinant E. coil at 10 mM, lower than that of parent strain (30 mM).