• Journal of the Korean Society for Marine Environment & Energy
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• v.7 no.3
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• pp.116-121
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• 2004

Treatability tests were conducted to study the feasibility of EMMC process as a recycling-water treatment system in high density seawater aquaculture farm. To study the effect of organic and ammonia nitrogen loading rate on system performance, hydraulic retention time was reduced gradually from 12hr to 10min. The conclusions are can be summarized as follows. When the system HRT was reduced from 12hr to 2hr gradually, there was little noticeable change(reduction) in ammonia nitrogen removal efficiencies. However, removal efficiencies were decreased dramatically when the system was operated under the HRT of less than 2hr. In case of organics(COD), there was no dramatic change in removal efficiencies depending on HRT reduction. COD removal efficiencies were maintained successfully higher than 9％ when the system was operated at tile HRT of 10 min. System performances depending on media packing ratio in the reactors were also evaluated. There were little differences in each reactor performances depending on media packing ratio in reactor when the reactors were operated under the HRT of longer than 1hr. However, differences in reactor performances were considerably evident when the reactors were operated under the HRT of shorter than 1hr. When comparing reactor performance among 25％, 50％,7 5％ packed reactor, it can be judged that media packing ratio more than 50％ plays no significant role in increasing reactor performance. For this reason, packing the media less than 50％ is more reasonable way in view of economic. Such a tendency shown in COD removal efficiencies well agreed with the variation of ammonia-nitrogen removal efficiencies according to the media packing ratio in reactors at each HRT. Difference in effluent ammonia-nitrogen concentration between 50％ media packing reactor and 75％ media packing reactor was negligible. When comparing with the results of 25％ packing reactor, difference was not so great.

• Journal of Microbiology and Biotechnology
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• v.11 no.6
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• pp.915-921
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• 2001

Phytase improves the bioavailability of phytate phosphorus in plant foods to humans and animals, and reduces the phosphorus pollution of animal waste. In order to express a high level of fungal phytase in Saccharomyces cerevisiae, various expression vectors were constructed with different combinations of promoters, translation enhancers, signal peptides, and terminator. Three different promoters fused to the phytase gene (phyA) from Aspergillus niger were tested: a galactokinase (GAL1) promoter, glyceraldehyde-3-phosphate dehydrogenase (GPD) promoter, and yeast hybrid ADH2-GPD promoter consisting of alcohol dehydrogenase II (ADH2) and a GPD promoter. The signal peptides of phytase, glucose oxidase (GO), and rice amylase 1A(RAmy1A) were included. Plus, the translation enhancers of the ${\Omega}$ sequence and UTR70 from the tobacco mosaic virus (TMV) and spinach, respectively, were also tested. Among the recombinant vectors, pGphyA06 containing the GPD promoter, the ${\Omega}$ sequence, RAmy1A, and GAL7 terminator expressed the highest phytase activity in a culture filtrate, which was estimated at 20 IU/ml. An intracellular localization of the expressed phytase activity in a culture filtrate, which was estimated at 20 IU/ml. An intracellular localization of the expressed phytase was also performed by inserting an endoplasmic reticulum (ER) retention signal, KDEL sequence, into the C-terminus of the phytase within the vector pHphyA-6. It appeared that the KDEL sequence directed most of the early expression of phytase into the intracellular compartment yet more than $60\%$ of the total phytase activity was still retained within the cell even after the prolonged (>3 days) incubation of the transformant. However, the intracellular enzyme activity of the transformant without a KDEL sequence was as high as that of the extracellular one, thereby strongly suggesting that the secretion of phytase in S. cerevisiae appeared to be the rate-limiting step for the expression of a large amount of extracellular recombinant phytase, when compared with other yeasts.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.7
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• pp.1067-1075
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• 2007

Twenty eight 3-4 month old castrated Black Bengal kids (Capra hircus) were used to determine the effects of source and level of dietary copper (Cu) concentration on their performance and nutrient utilization. Cu was supplemented (0, 10, 20 and 30 mg/kg diet DM) as copper sulfate ($CuSO_4$, $5H_2O$) or copper proteinate (Cu-P). Kids were fed a basal diet containing maize (19.5%), soybean (17.0%), deoiled rice bran (56.5%), molasses (4.0%), di-calcium phosphate and salt (1.0% each) and mineral and vitamin mixture (0.5% each) supplements at 3.5% of body weight to meet NRC (1981) requirements for protein, energy, macro minerals and micro minerals, excluding Cu. The basal diet contained 5.7 mg Cu/kg, 122.5 mg Fe/kg, 110 mg Zn/kg, 0.26 mg Mo/kg and 0.32% S. $CuSO_4$ or Cu-P was added to the basal diet at the rate of 10, 20 and 30 mg/kg. Kids were housed in a well ventilated shed with facilities for individual feeding in aluminum plated metabolic cages. Blood samples were collected from the jugular vein on d 0, 30, 60 and 90 to determine hemoglobin (Hb), packed cell volume (PCV), total erythrocyte count (TEC), total leukocyte count (TLC) and serum enzymes (alkaline phosphatase, alanine transferase and aspertate transferase). A metabolism trial of 6 days duration was conducted after 90 days of experimental feeding. Statistical analysis revealed that source and level of Cu supplementation improved live weight gain (p<0.04) and average daily gain (p<0.01). No significant contribution of source and level of Cu to alter serum serum enzymes was evident. Goats fed Cu-P tended to have higher Hb, PCV and TEC than with $CuSO_4$ supplementation. Cu-P increased digestibility of ether extract (EE, p<0.02) and crude fiber (p<0.05) and showed an increasing trend (p<0.09) for digested crude protein (CP) and crude fiber (CF). Supplemental dose of Cu linearly improved (p<0.02) digestibilities of dry matter (DM), organic matter (OM), EE and nitrogen free extract (NFE). Though the absorption of nitrogen (N) was not affected (p>0.10) by both source and dose of Cu, N retention was affected (p<0.04) and there was a significant $Source{\times}Dose$ interaction (p<0.05). Final body weight (BW) was not influenced (p>0.10) by the source of Cu but increasing dose of Cu increased (p<0.04) the BW of kids. TDN intake (g/kg $W^{0.75}$) was higher (p<0.05) with the increased dose of Cu and there was a significant $Source{\times}Dose$ interaction. It was concluded that supplementation of Cu from different sources and varying dose level in a concentrate based diet may improve performance, nutrient utilization and plane of nutrition in castrated Black Bengal kids. The effects on performance and nutrient utilization are more pronounced with Cu-P than $CuSO_4$ supplementation. Higher dose of Cu showed better result than lower dose.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.6
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• pp.434-441
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• 2009

The effect of varying sulfate concentration on continuous fermentative hydrogen production was studied using enriched mixed microflora in continuously fed reactor. Glucose was used as a model substrate for carbohydrates, and hydraulic retention time (HRT) was maintained at 1, 0.5, 0.25 day, respectively. Sulfate concentration was 0${\sim}$20,000 mg/L and the operating pH was maintained at 5.5. The experimental results indicate that hydrogen production is not affected by high sulfate concentration and shorter HRT of 0.25 day enhance hydrogen production. At HRT 1, 0.5, 0.25 day, the hydrogen production rate and hydrogen yield were 2.6, 4.6, 9.4 L/day, and 2.0, 1.8, 1.6 mol $H_2$/mol glucose, respectively. Residual sulfate content was 96${\sim}$98, 95${\sim}$97, and 94${\sim}$97% at HRT 1, 0.5, 0.25 day which show that no sulfate reduction occurred in the reactor during the experiments. Results of Fluorescence In Situ Hybridization (FISH) may indicate the presence of HPB (hydrogen producing bacteria) under all experimental conditions. However, SRB (sulfate reducing bacteria) were not found.

• Analytical Science and Technology
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• v.5 no.4
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• pp.389-399
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• 1992

Liquid Chromatographic behavior of Pd(II) in Isonitrosoethylacetoacetate lmine, $Pd(IEAA-NR)_2$ (R=H, $CH_3$, $C_2H_5$, $n-C_3H_7$, $C_6H_5-CH_2$, $n-C_4H_9$) chelates were investigated by reversed-phase HPLC on Micropak MCH-5 column using methanol/water as mobile phase. The optimum conditions for the separation of $Pd(IEAA-NR)_2$ chelates were examined with respect to the effect of the flow rate, sample solvent, mobile phase strength and column temperature. It wass found that metal chelates were properly eluted in an acceptable range of capacity factor value($0{\leq}log\;k^{\prime}{\leq}1$). The dependence of the logarithm of capacity factor(k') on the volume fraction of water in the binary mobile phase was examined. Also, the dependence of k' on the liquid-liquid extration distribution ratio($D_c$) in methanol-water/n-alkane extration system was investigated. Both kinds of dependence are linear, which susggests that the retention of the electroneutral metal chelate is largely due to the solvophobic effect. Standard adsorption enthalpy changes (${\Delta}H^{\circ}$) and standard adsorption entropy changes (${\Delta}S^{\circ}$) of Pd(II) Isonitrosoethylacetoacetate imine chelates on Micropak MCH-5 column were calculated by measuring capacity factor with changing temperature of the column.

• Applied Biological Chemistry
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• v.36 no.4
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• pp.265-270
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• 1993

In order to retain the freshness of fruits and vegetables and to reduce the rate of disease damage, grafruit seed extract (GPSE), natural microorganism control agent, was applied during the preservation process of fresh fruits and vegetables. GFSE showed an effective inhibitory action against plant putrefactive bacteria and fungi which were involved in the decay of fruits and vegetables. Minimal inhibitory concentrations for GFSE against the microbes were in the range of 50 to 2,000 ppm. Direct observation of microbial cells and spores using electron microscopy showed their function was destroyed by the treatment of the dilute solutions of GFSE. Fresh Welsh onions, onions and red peppers treated with GFSE and stored in polyethylene film (0.1 mm) retained better quality in color and texture than the non-treated control. GFSE was efficient in controlling the germination of potatoes. It was observed that GFSE would reduce disease damages and have bactericidal and fungicidal properties during the storage of such fruits and vegetables as zucchinis, cucumbers, tomatoes and mandarin oranges.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.2
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• pp.140-148
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• 1994

Indentification of IMP was carried out and changes in ATP breakdown products during storage at $0^{\circ}C\;ad\;20^{\circ}C$ were investigated in the muscles of ascidian Halocynthia roretzi. For identifying IMP, the ion-exchange column chromatographic method was applied to the perchloric acid extract of the muscle of cultured ascidian collected at the southern coast near Chungmu of Korea in April 1989. The IMP of sample was eluted a little earlier than that of the reference standard, but absorption spectra of both fractions agreed each other. In addition, both fractions gave the identical retention time of HPLC. These results reconfirmed that the ascidian muscle did contain IMP, indicating that ATP was degraded through IMP breakdown pathway, such as $ATP{\to}ADP{\to}AMP{\to}IMP{\to}Ino{\to}Hyp$. Ado was detected in some samples and IMP was detected throughout the experimental periods at both temperatures, but their levels were always very low; they did not increase significantly even when the decreasing rate of AMP was very rapid and concomitant remarkable increase in Ino were observed at the early stage of storage. Those changes in ATP suggest that AMP deaminase activity was present in the ascidian muscle, though it was very low. The main breakdwon pathway of ATP was assumed to be $ATP{\to}ADP{\to}AMP{\to}Ado{\to}Ino{\to}Hyp$. In conclusion, there were two breakdown pathways of ATP in the muscle of ascidian as was the case for the muscle of many marine crustaceans.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.3
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• pp.117-127
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• 2016

In this study, analyzed scenarios of the environmental instream flow for water quality improvement in Saemangeum watershed. In order to get an environmental instream flow, Methodology is selected for Retention-Basin, reservoir expansion, new dam construction, Modification of water intake and drainage system, Rearrangement of plan for system which Yongdam and Seomjin river dam have been used water supply. The study composed of diverse scenario of Environmental instream flow increasement and analyzed the effect of improving the water quality by the QUAL2K model and calculation of runoff for saemangeum watershed by SWAT model. The following water quality indicators have been simulated in irrigation and non-irrigation period for BOD and T-P. When scenarios applied to water quality model, Improvement rate in the water quality for Total Maximum Daily loads of Mankyung B unit watershed during irrigation and non-irrigation period is BOD (28.70%), T-P (17.09%) and BOD (28.51%), T-P (28.68%) respectively. Dongjin A unit watershed during irrigation and non-irrigation period is BOD (14.39%), T-P (14.59%) and BOD (15.54%), T-P (19.46%) similary. Simulation results is to quantify the constribution of the improvement in the water quality. In particular, It was demonstrative that improving effect for water quality was evaluated to be great in non-irrigation period.

• The Journal of the Korea Contents Association
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• v.18 no.3
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• pp.256-264
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• 2018

The purpose of this study was to investigate the relationship between oral health behaviors and the results of the oral dysentery test for dental hygienists and students at Gyeonggi - do and Chungcheongnam - do. Self - filling questionnaires and oral diseases. The following conclusions were obtained. The most common toothbrushing frequency was three times a day (60.2%), and the most dominant frequency of eating between meals was once or less(49.7%). The most common snack that they had was stickiness-free sweetened food(66.5%), and the type of beverage that they had the most was sweetened beverages(49.7%). The average stimulated saliva flow rate was 9.41ml, and they got a mean of 9.52 in the buffering capacity of saliva. The average glucose clearance time was a mean of 12.02. When they took a streptococcus mutans colony count test, 80.1 percent belonged to the low-risk group(<$10^5$), and 82.6 percent belonged to the low-risk group(<$10^5$) when a lactobacillus test was conducted. There was a positive correlation between the irritant saliva fraction and the non-irritating saliva and saliva buffering ability. In the fluoride application experience, the glucose retention time was 10.66 minutes and the fluoride application experience was 13.33 minutes. (P = .008). The importance of oral health, which is directly linked to general health, should be emphasized in order to improve the quality of life as well as the life expectancy. For oral health, which is directly linked to systemic health, it is necessary to provide opportunities for oral health education that can be easily accessed by the public, and to continuously develop and provide oral health care programs for a lifetime.

• Journal of Veterinary Clinics
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• v.26 no.1
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• pp.23-28
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• 2009

Peritoneal dialysis (PD) is a clinical technique that therapeutically removes toxic solutes from body fluids and normalizes endogenous solutes whose aberrant concentrations disrupt normal physiology. This study retrospectively evaluated clinical outcomes and complications of PD in 20 dogs with renal failure. Blood works (total count of red blood cells (RBC), packed cell volume (PCV), the serum biochemical, and electrolyte values related to renal insufficiency) and complications associated with peritoneal dialysis, and clinical outcomes were recorded before and after PD. Additionally, creatinine reduction ratio (CRR) and urea nitrogen reduction ratio (URR) were calculated for evaluating the efficacy of PD. PD resulted in a significant (p < 0.05) reduction in blood urea nitrogen (BUN) concentration in 19 dogs, while a significant (p < 0.05) reduction in creatinine concentration in 17 dogs. The complications of PD were hypoalbuminemia (12/20, 60%), anemia (10/20, 50%), subcutaneous dialysate leakage (9/20, 45%), bacterial peritonitis (6/20, 30%), dialysate retention (5/20, 25%) and limb edema (4/20, 20%). This study demonstrated that PD was effective in reducing the magnitude of azotemia in dogs with renal failure especially in acute phase, although the complication rate was high but manageable.