• Korean Chemical Engineering Research
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• v.52 no.1
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• pp.88-91
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• 2014

In this study, oil as a source of biodiesel from Nannochloropsis oceanica was extracted using organic solvent. The oil extraction yield and efficiency from dry and wet microalgae were investigated. The initial fatty acids content of the N. oceanica was 317.8 mg/g cell showing a high oil content over 30%. The yield from dry microalgae was higher than that from wet microalgae due to the inhibition of water. The yield by chloroform-methanol was the highest and the yield by hexane was the lowest. However, the total fatty acids contents with the chloroform-methanol were 678.7 and 778.2 mg/g oil under dry and wet conditions, respectively. The high oil extraction yield by chloroform-methanol reflected the fact that the extracted oil contained a high level of impurity. The hexane-methanol extraction from dry N. oceanica showed high oil extraction efficiency, 82.6%. The chloroform-methanol extraction under wet condition also showed high efficiency, 88.0%. While the hexane-methanol extraction from dry microalgae is desirable under low drying cost, the chloroform-methanol extraction from wet microalgae is desirable under high drying cost.

• Korean Chemical Engineering Research
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• v.55 no.6
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• pp.798-806
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• 2017

A activated carbon (WCAC, waste citrus activated carbon) prepared from an agricultural waste citrus peel material generated in Jeju was utilized for the removal of dimetridazole (DMZ) antibiotics in aqueous solution. The adsorption of DMZ on WCAC was investigated with the change of various parameters such as contact time, dosage of WCAC, particle size of WCAC, temperature, pH, and DMZ concentration. The DMZ adsorption capacity increased with increasing temperature and decreasing particle size. Also it was decreased at less than pH 4 but sustained almost constantly at pH 4 or greater. Isotherm parameters were determined from the Langmuir, Freundlich, Redlich-Peterson and Duinin-Radushkevich (D-R) isotherm models. The isotherm data were best described by the Redlich-Peterson isotherm model. And the adsorption kinetics can be successfully fitted to the pseudo-second-order kinetic model. The results of the intra-particle diffusion model suggested that film diffusion and intra-particle diffusion were occurred simultaneously during the adsorption process. Meanwhile, the thermodynamic parameters indicated that the adsorption reaction of DMZ on WCAC was an endothermic and spontaneous process. The experimental results showed that WCAC is a promising and cheap adsorbent for the removal of DMZ antibiotics.

• Korean Chemical Engineering Research
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• v.55 no.6
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• pp.807-815
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• 2017

This study investigated the removal efficiency of residual pentane from paclitaxel according to the drying temperature in the case of rotary evaporation, and performed a kinetic and thermodynamic analysis of the drying process. At all the temperatures (25, 30, 35, 40, and $45^{\circ}C$), a large amount of the residual solvent was initially removed during the drying, and the drying efficiency increased when increasing the drying temperature. Five drying models (Newton, Page, modified Page, Henderson and Pabis, Geometric) were then used for the kinetic analysis, where the Henderson and Pabis model showed the highest coefficient of determination ($r^2$) and lowest root mean square deviation (RMSD), indicating that these models were the most suitable. Furthermore, in the thermodynamic analysis of the rotary evaporation, the activation energy ($E_a$) was 4.9815 kJ/mol and the standard Gibbs free energy change (${\Delta}G^0$) was negative, whereas the standard enthalpy change (${\Delta}H^0$) and standard entropy change (${\Delta}S^0$) were both positive, indicating that the drying process was spontaneous, endothermic, and irreversible.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.7
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• pp.912-919
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• 2017

Objective: Identification of the candidate genes that play key roles in phenotypic variations can provide new information about evolution and positive selection. Interleukin (IL)-32 is involved in many biological processes, however, its role for the immune response against various diseases in mammals is poorly understood. Therefore, the current investigation was performed for the better understanding of the molecular evolution and the positive selection of single nucleotide polymorphisms in IL-32 gene. Methods: By using fixation index ($F_{ST}$) based method, IL-32 (9375) gene was found to be outlier and under significant positive selection with the provisional combined allocation of mean heterozygosity and $F_{ST}$. Using nucleotide sequences of 11 mammalian species from National Center for Biotechnology Information database, the evolutionary selection of IL-32 gene was determined using Maximum likelihood model method, through four models (M1a, M2a, M7, and M8) in Codeml program of phylogenetic analysis by maximum liklihood. Results: IL-32 is detected under positive selection using the $F_{ST}$ simulations method. The phylogenetic tree revealed that goat IL-32 was in close resemblance with sheep IL-32. The coding nucleotide sequences were compared among 11 species and it was found that the goat IL-32 gene shared identity with sheep (96.54%), bison (91.97%), camel (58.39%), cat (56.59%), buffalo (56.50%), human (56.13%), dog (50.97%), horse (54.04%), and rabbit (53.41%) respectively. Conclusion: This study provides evidence for IL-32 gene as under significant positive selection in goat.

• Asia-Pacific Journal of Business
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• v.1 no.2
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• pp.83-106
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• 2010

The purpose of this study is to examine how perceived service quality influences perceived uncertainty, customer satisfaction, relation quality and loyalty, and in turn, provides insight for Korean banks when they penetrate into the Chinese marketplace. The findings are as followed. First, Perceived uncertainty has an important mediating role in the relation between perceived service quality and customer satisfaction. Second, perceived service quality has a direct effect on customer satisfaction, customer satisfaction has an important mediating role in the relationship between perceived service quality and relationship quality. Third, perceived uncertainty has a direct effect on customer satisfaction, but is significantly negative. Customer satisfaction has an important mediating role in the relationship between perceived uncertainty and relationship quality. Fourth, relationship quality has a direct effect on attitudinal loyalty and behavioral loyalty.

• The Korea Journal of Herbology
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• v.26 no.4
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• pp.169-180
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• 2011

Objectives : This study aimed at evaluation of the effects of Rhodiola rosea on brain edema and expressions of matrix metalloproteinases (MMPs) related to blood-brain barrier (BBB) disruption. Methods : Brain edema following intracerebral hemorrhage (ICH) was induced by the stereotaxic intrastriatal injection of bacterial collagenase type VII in rats (Sprague-Dawley). Then ethanol extract of Rhodiola rosea was treated once a day for 3 days. Brain edema % and water contents, and BBB leakage were examined. Immunohistochemistry was processed for MMP-9, MMP-12, and iNOS expressions in the brain sections and each immuno-labeled cells were analyzed with image analysis software. Results : 1. Ethanol extract of Rhodiola rosea reduced brain edema following ICH in rats significantly. 2. Ethanol extract of Rhodiola rosea reduced excessive brain tissue water contents following ICH in rats significantly. 3. Ethanol extract of Rhodiola rosea reduced BBB leakage in the cerebral cortex following ICH in rats. 4. Ethanol extract of Rhodiola rosea reduced cellular edema of neurons in peri-hematoma and the cerebral cortex following ICH in rats significantly. 5. Ethanol extract of Rhodiola rosea reduced MMP-9 positive cells in the cerebral cortex following ICH in rats significantly. 6. Ethanol extract of Rhodiola rosea reduced MMP-12 positive vessels in the cerebral cortex following ICH in rats significantly. 7. Ethanol extract of Rhodiola rosea reduced iNOS positive cells in the cerebral cortex and external capsule following ICH in rats significantly. Conclusions : These results suggest that Rhodiola rosea reveals protective effect against brain edema and cytotoxic edema of neurons by means of down-regulation of MMPs and iNOS expressions, and inhibition of BBB leakage.

• Journal of the Economic Geographical Society of Korea
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• v.15 no.2
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• pp.332-342
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• 2012

The current research aims at classifying the bus stops as transfer center in order to establish the rational bus transfer systems. Existing research typically identifies characteristics of demands for bus stops and land use surrounding the bus stops and classifies and profiles the bus stops. A common problem with this type of research is that the results with cross-sectional characteristics of land use and bus stop usage do not capture the details of trip chain, the fundamental characteristics of the trips with transfer. This paper therefore examines bus stop classifications with such variables as transport mode chains, intermediate stop chains and timing chains. The analysis on the data collected on Monday 20 April 2009 for passengers of Gyeong-gi bus results in a clear classification among bus stops in terms of such trip chain variables. The research would provide useful information for the decision support of transfer stops location choice and infrastructure design.

• Korean journal of applied entomology
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• v.23 no.1 s.58
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• pp.49-55
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• 1984

This study was carried out to investigate the biological performance of the brownplanthopper, Nilaparvata lugens Stal, reared on rice plants at different growth stages; maximum tillering, booting, heading with and without panicles, and milking. The results obtained are as follows: The rice plants at the maximum tillering stage gave the best in the longevity, oviposition period, and the total number of oviposited eggs for the macropterous females, and the worst with the booting stage. For the brachypterous females, however, the best results were obtained from the rice of which their panicles had removed after heading. There was no significant difference in the hachability of eggs and the developmental period of the nymphs in the next generation, but the nymphal mortality was the highest with the milking stage and the lowest with the maximum tillering and heading stage without panicles. The longest life span was shown in males derived on the maximum tillering stage, and the shortest for milking(macropterous type) or booting (brachypterous type) stages. Coefficientes of variances in longevity and number of eggs for the adults emerged from heading stage without panicles were lower than those with panicles intact, and such trend was more obvious in brachypterous adults, especially for the females. The biological performances of the BPH have close relationship with the translocated organic material at the feeding site which showed considerable difference with the growth stages of the rice.

• Applied Biological Chemistry
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• v.30 no.2
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• pp.109-117
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• 1987

Three rice varieties of Akibare (japonica), Milyang 30 (indica) and Taebaeg (indica) were investiated for sensory and physical qualities of cooked rices during storage at the temperature range of $4^{\circ}C$ and $70^{\circ}C$ for 25 hours. The qualities studied were sensory attributes of odor, taste and appearance which were evaluated by multiple comparison method. The other properties were size of rice granule and separation Property of individual cooked rices in water. The sensory results showed that all of the descriptions except moldy odor and oily taste were scored higher values for cooked rices of Akibare than those values of Milyang 30 and Taebaeg. It was found that storage of cooked rices at various temperatures resulted a significant decrease in most of sensory qualities except moldy odor and oily taste which were rather increased. The quality change was more affected at storage at low temperature, particularly at $4^{\circ}C$, than at higher temperatures. The property of individual separation of cooked rices in water for freshly cooked rices showed that Akibare was separated 44.4% after 1 minute shaking while Milyang 30 and Taebaeg had the higher separation value of 53.1%, and 51.0%, respectively. This characteristic was noticeably reduced after 3 hours storage and then steady increased during further storage. It was also found that the separation percent was generality increased as the storage temperature increased from $4^{\circ}$ to $70^{\circ}C$.

• Applied Biological Chemistry
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• v.30 no.2
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• pp.118-125
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• 1987

Three rice varieties of Akibare (japonica), Milyang 30 (indica) and Taebaeg (indica) were investigated for their changes in sensory and physical qualities of cooked rices during storage at the temperature range of $4^{\circ}C$ and $70^{\circ}C$ for 25 hours, The qualities studied were sensory attributes of texture which were evaluated by multiple comparison method and physical characteristics of texture measured using with rheometer. Physical Properties of hardness, adhesiveness and elasticity of cooked rices were found to be different among the rice varieties and were affected by storage conditions. Higher values in hardness and elasticity and lower values in adhesiveness were measured for cooked rices of Akibare immidiately after cooking. Those physical values were changed by a steady decrease in hardness and elasticity and increase in adhesiveness during storage for 25 hours. Correlations between sensory and physical characteristics of texture was found a significant relationships between gumminess and hardness (r=0.696), gumminess and adhesiveness (r=-0.800) and gumminess and elasticity (r=0.806).