• Journal of Wetlands Research
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• v.9 no.2
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• pp.71-84
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• 2007

Masan Bay is a representative semi-closed bay acted as a sedimentation reservoir with a slow current velocity and a poor water circulation in Korea. The pollutants from terrestrial sources into the Masan Bay have apparently environmental pollution problems, such as eutrophication, red tied, and hypoxia. In this study, An ecological modeling work was performed to estimate the material circulation including the growth of bivalve in ecosystem. Furthermore, the effect of water purification was calculated by filter feeding bivalve to particulate organic matter just like COD and phytoplankton. And Water quality management strategy by bio-purification of bivalve is derived through selection of location, quantification of bivalve aquaculture farm. The results showed that the optimum location for bivalve farming is where phytoplankton accumulation by physical processes is maximized and the optimum density and area of bivalve are 35 individuals $m^{-3}$ and ca. 500 hectare, respectively. When assuming conditions for the optimum growth of bivalve, COD could decrease by up to 18% even without other reduction of pollution loads.

• KSBB Journal
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• v.19 no.3
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• pp.192-199
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• 2004

In this work the production of glutathione (GSH) by yeast Saccharomyces cerevisiae and the monitoring of the process were studied. In shaking culture the production of GSH was high at initial pH value of 4 and at temperature of 30$^{\circ}C$. But when L-cysteine was added to the culture medium at the beginning of the cultivation, the productivity of GSH was low. In case 0,5% (v/v) of L-cysteine, glycine and glutamic acid were introduced to the culture medium in the exponential cell growth phase, high concentration of GSH (about 90 mg/L) was produced in the bioreactor. A fed-batch operation with stepwise glucose feeding strategy allowed to produce 102 mg/L of GSH. The cultivation processes were on-line monitored by a 2-dimensional fluorescence sensor. A few off-line data such as cell growth, cystein concentration, phosphate concentration and GSH productivity could be well correlated to the fluorescence intensity of some combinations of excitation and emission wavelengths.

• Korean Journal of Organic Agriculture
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• v.27 no.2
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• pp.225-235
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• 2019

The present study hypothesized that ratio between carcass traits components could be applied for the understanding of yield index in Hanwoo steer. A thousand data was generated based on average carcass weight (CW), loin area (LA) and backfat thickness (BT) of Hanwoo steer in December 2018 for analysis 1. Then yield index (YI) was calculated using newly established yield index equation. The correlation between yield index and each carcass traits was visualized. In the interaction between carcass traits components (LA, CW, BT) and YI, only the interactions including BT showed a regular pattern to YI. Then changes of YI according to ratio of carcass traits components were investigated. The observed interactions between LABT and CWBT were similar with Monod equation model. The changes of YI to LABT and CWBT were fitted to Monod equation, and yield constants (K1 for LABT; K2, CWBT) of each equation were calculated as 0.47 and 2.20, respectively. Carcass traits from 5 commercial Hanwoo steer farm were then employed in the second analysis. Yield constants of each farm were estimated. In estimation, R² value for K1 (LABT) showed greater than the K2 (CWBT). Finally, each farm was plotted based on their K1 and K2 values and it was found that greater yield index of Hanwoo steer was found as increased K1 and K2. As conclusion, the present study suggested the possibility of K1 and K2 values for understanding of yield grade equation and their application in the evaluation of new model for yield grade estimation and feeding strategy.

• Journal of Chest Surgery
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• v.53 no.2
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• pp.41-48
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• 2020

Background: Chylothorax after congenital heart surgery is not an uncommon complication, and it is associated with significant morbidity. However, consensus treatment guidelines are lacking. To improve the treatment outcomes of patients with postoperative chylothorax, we implemented a standardized management protocol at Severance Hospital in September 2014. Methods: A retrospective review of patients treated at a single center was done. All corrective and palliative operations for congenital heart disease performed at our institution between January 2008 and April 2018 were reviewed. The incidence and treatment outcomes of postoperative chylothorax were analyzed. Results: The incidence of chylothorax was 1.9%. Sixty-one percent of the patients could be managed with a low-fat diet, while 28% of the patients required complete restriction of enteral feeding. Thoracic duct embolization was performed in 2 patients and chest tube drainage decreased immediately after the procedure. No patient required thoracic duct ligation or pleurodesis. After implementation of the institutional management protocol, the number of chest tube drainage days decreased (median, 24 vs. 14 days; p=0.45). Conclusion: Implementing a strategy to reduce postoperative chylothorax resulted in an acceptable incidence of postoperative chylothorax. Instituting a clinical practice protocol helped to curtail the treatment duration and to decrease the requirement for surgical treatment. Image-guided embolization of the thoracic duct is an effective treatment for postoperative chylothorax.

• Journal of Environmental Impact Assessment
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• v.26 no.3
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• pp.207-216
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• 2017

Several bioassays have been performed for assessment of the impact of polluted sediments. The direct exposure method using sediments is limited by difficulty controlling feeding and its effects on organisms. Furthermore, only macro-organisms and benthic organisms are used. To evaluate the potential application of sediment elutriate as a complementary strategy for impact assessment, copepods, small organisms with a short life cycle, were exposed to sediment elutriates, and several end-points were measured. As a result, sediment elutriates prepared from polluted sites caused growth retardation in marine copepods. In terms of molecular biomarkers, antioxidant-related and chaperone protein gene expression levels were increased in a dose- and time-dependent manner. Thus, we suggest that sediment elutriate tests can provide an effective alternative for toxicity assessment using whole sediment samples. Further studies are required to obtain sufficient data for future applications.

• Journal of The Korean Society of Grassland and Forage Science
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• v.37 no.1
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• pp.50-55
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• 2017

In attempt to avoid crop damage through wild bird's picking, this study was designed with aim to evaluate several pre-sowing soybean seed coatings for optimum yield in corn-soybean mixed forage. It was investigated under four cropping treatments, viz. 1) corn sole, 2) corn mixed with soybean without any coating, 3) corn with iron coated soybean and 4) corn with thiram coated soybean. Each treatment had three replicates and corn sole was control treatment. Pioneer (P1184) and crossbred ($PI483463{\times}Hutcheson$) seeds were used for corn and soybean, respectively. The trial was conducted under randomized block design from $5^{th}$ June to $23^{rd}$ September, 2015. Data were an alyzed through ANOVA technique using SAS9.1.3 software. Results depicted that survivability of soybean against wild birds damage was found better (p<0.05) in thiram coating which was higher than iron coating and control treatment but later on thiram coating had adverse effects on subsequent growth of soybean plants. Corn stalk height was decreased (p<0.05) in thiram coating, whereas corn ear height was reduced in iron coating treatment. Iron coating enhanced (p<0.05) height of soybean plant (p<0.05) better than that of thiram coating. Soybean seed coatings didn't influence dry matter yield and nutritive value in terms of total digestible nutrients yield in corn soybean mixed forage. Conclusively, although presowing thiram coating enhanced survivability of soybean plants against wild bird damage but had adverse effects on its subsequent growth. However, soybean seed coatings didn't influence yield and nutritive value of corn soybean intercropping forage.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.1
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• pp.48-53
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• 2006

The asymmetric biosynthesis of ethyl (S)-4-chloro-3-hydrobutanoate from ethyl 4-chloro-3-oxobutanoate was investigated by using whole cells of Candida magnoliae JX120-3 without the addition of glucose dehydrogenase or $NADP^+/NADPH$. In a one-phase system, the bioconversion yield was seriously affected on the addition of 12.1 g/L ethyl 4-chloro-3-oxobutanoate. In order to reduce this substrate inhibition, a water/ n-butyl acetate two-phase system was developed, and the bioreduction conditions optimized with regard to the yield and product enantiometric excess value. The optimal conditions were as following: water to n-butyl acetate volume ratio of 1:1, 4.0 g DCW/L active cells, 50 g/L glucose and $35^{\circ}C$. By adopting a dropwise substrate feeding strategy, high concentration of ethyl 4-chloro-3-oxobutanoate (60 g/L) could be asymmetrically reduced to ethyl (S)-4-chloro-3-hydrobutanoate with high yield (93.8%) and high enantiometric excess value (92.7%).

• Clinical and Experimental Pediatrics
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• v.59 no.4
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• pp.165-173
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• 2016

Purpose: To identify the effects of modified parenteral nutrition (PN) and enteral nutrition (EN) regimens on the growth of very low birth weight (VLBW) infants. Methods: The study included VLBW infants weighing <1,500 g, admitted to Chungnam National University Hospital between October 2010 and April 2014, who were alive at the time of discharge. Subjects were divided according to 3 periods: period 1 (n=37); prior to the PN and EN regimen being modified, period 2 (n=50); following the PN-only regimen modification, period 3 (n=37); following both PN and EN regimen modification. The modified PN regimen provided 3 g/kg/day of protein and 1 g/kg/day of lipid on the first day of life. The modified EN regimen provided 3.5-4.5 g/kg/day of protein and 150 kcal/kg/day of energy. We investigated growth rate, anthropometric measurements at 40 weeks postconceptional age (PCA) and the incidence of extrauterine growth restriction (EUGR) at 40 weeks PCA. Results: Across the 3 periods, clinical characteristics, including gestational age, anthropometric measurements at birth, multiple births, sex, Apgar score, surfactant use and PDA treatment, were similar. Growth rates for weight and height, from time of full enteral feeding to 40 weeks PCA, were higher in period 3. Anthropometric measurements at 40 weeks PCA were greatest in period 3. Incidence of weight, height and head circumference EUGR at 40 weeks PCA decreased in period 3. Conclusion: Beginning PN earlier, with a greater supply of protein and energy during PN and EN, is advantageous for postnatal growth in VLBW infants.

• Journal of Ecology and Environment
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• v.30 no.2
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• pp.109-119
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• 2007

The effect of water flow on the growth of Gafrarium tumidum was studied in the field using open cages constructed with stainless steel net and perspex in which holes were drilled. Cages with different flows (25, 50 and 75% of the control) were made by varying the area of perspex being drilled. Reduction in flow rate was directly proportional to the undrilled area, and the mean flow rate of the different treatment groups varied from 3.12 cm/s for the 25% exposure to 12.48 cm/s for the control cages. At the end of the 3-month experiment, no significant differences in sediment characteristics were found among the treatments. Growth in shell length, shell weight and tissue dry weight was, however, positively correlated with flow rate. Percentage increases ranged from $3.0{\sim}8.3%$ for shell length, $9.9{\sim}23.1%$ for shell weight and $17.2{\sim}53.3%$ for tissue dry weight. Condition index of the clam was not significantly different among the treatments. Seston depletion effect could reduce growth in G. tumidum only when water flow was reduced to 25% of the control. G. tumidum also exhibited different responses in shell and tissue growth at low flow rates, in which shell growth continued to decrease as flow rate decreased whereas tissue growth was relatively independent of low flows at 25 and 50% of the control. It was suggested that when seston flux was reduced at slow flows, it would be a better strategy for G. tumidum to channel energy for gonad development instead of shell growth during the reproductive stage.

• The Journal of Korean Academic Society of Nursing Education
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• v.27 no.2
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• pp.175-185
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• 2021

Purpose: The aim of this study was to identify core keywords and topic groups in the 'Gestational diabetes mellitus (GDM) and Breastfeeding' field of research for better understanding research trends in the past 20 years. Methods: This was a text-mining and topic modeling study composed of four steps: 1) collecting abstracts, 2) extracting and cleaning semantic morphemes, 3) building a co-occurrence matrix, and 4) analyzing network features and clustering topic groups. Results: A total of 635 papers published between 2001 and 2020 were found in databases (Web of Science, CINAHL, RISS, DBPIA, RISS, KISS). Among them, 3,639 words extracted from 366 articles selected according to the conditions were analyzed by text network analysis and topic modeling. The most important keywords were 'exposure', 'fetus', 'hypoglycemia', 'prevention' and 'program'. Six topic groups were identified through topic modeling. The main topics of the study were 'cardiovascular disease' and 'obesity'. Through the topic modeling analysis, six themes were derived: 'cardiovascular disease', 'obesity', 'complication prevention strategy', 'support of breastfeeding', 'educational program' and 'management of GDM'. Conclusion: This study showed that over the past 20 years many studies have been conducted on complications such as cardiovascular diseases and obesity related to gestational diabetes and breastfeeding. In order to prevent complications of gestational diabetes and promote breastfeeding, various nursing interventions, including gestational diabetes management and educational programs for GDM pregnancies, should be developed in nursing fields.