• Ecology and Resilient Infrastructure
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• v.5 no.3
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• pp.163-173
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• 2018

The biopolymer (BP) used in this study is mainly composed of xanthan gum and ${\beta}$-glucan derived from microorganism and has been introduced as a novel material for soil stabilization. However, the broad applicability of BP has been suggested in the field of geotechnical engineering while little information is available about the effects of BP on the vegetation. The goal of this study is to find the BP effects on the growth of Camelina sativa L. (Camelina) under drought condition. For more thorough evaluation of BP effects on the plant growth, we examined not only morphological but also physiological traits and gene expression patterns. After 25 days of drought treatment from germination in the soil amended with 0, 0.25, 0.5, and 1% BP, we observed that the BP concentration was strongly correlated the growth of Camelina. When plants were grown under drought stress, Camelina in 0.5% BP mixture showed better physiological parameters of the leaf stomatal conductance, electrolyte leakage and relative water content compared to those in control soil without BP. Plant recovery rate after re-watering was higher and the development of lateral root was lower in BP amended soil. RNA expression of Camelina leaf treated with/without drought for 7 and 10 days showed that aquaporin genes transporting solutes at bio-membrane, CsPIP1;4, 2;1, 2;6 and TIP1;2, 2;1, were induced more in the plants with BP amendment and drought treatment. These results suggest that the soil amended with BP has a positive effect on the transport of nutrients and waters into Camelina by improving water retention in soil under drought condition.

• Journal of Yeungnam Medical Science
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• v.8 no.2
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• pp.128-137
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• 1991

Peritoneal dialysis has been widely considered to be the dialytic treatment of choice for acute renal failure in infants and young children, because the technique is simple, safe and easily adapted for these patients. Also peritoneal dialysis in infants might have more effective ultrafiltration and clearance than in adults. In certain circumstances associated with hemodynamic instability, ordinary volume peritoneal dialysis(30-50 ml/kg body weight per exchange) or hemodialysis may not be suitable unfortunately. But frequent cycled, low volume, high concentration peritoneal dialysis may be more available to manage the hemodynamically untable acute renal failure of newborns and infants. Seven infants underwent peritoneal dialysis for hemodynamically unstable acute renal failure with low exchange volume($14.2{\pm}4.2ml/kg$), short exchange time(30 to 45 minutes) and hypertonic glucose solution(4.25% dextrose). Age was $1.9{\pm}1.3$ months and body weight was $4.6{\pm}1.6kg $. Etiology of acute renal failure was secondary to sepsis with or without shock(5 cases) and postcardiac operation(2 cases). Catheter was inserted percutaneously with pigtail catheter or Tenkhoff catheter by Seldinger method. Dialysate was commercially obtained Peritosol which contained sodium, chloride, potassium, magnesium, lactate and calcium. Net ultrafiltration(ml/min) showed no difference between low volume dialysis and control($0.27{\pm}0.09$ versus $0.29{\pm}0.09$) Blood BUN decreased from $95.7{\pm}37.5$ to $75.7{\pm}25.9mg/dl$ and blood pH increased from $7.122{\pm}0.048$ to $7.326{\pm}0.063$ after 24 hours of peritoneal dialysis. We experienced hyperglycemia which were controlled by insulin(2 episodes), leakage at the exit site(2), mild hyponatremia(1) and Escherichia coli peritonitis(1). Two children of low volume dialysis died despite the treatment. In our experience, low volume and high concentration peritoneal dialysis with frequent exchange may have sufficient ultrafiltration and clearance without significant complications in the certain risked acute renal failure of infants.

• Korean Journal of Food Science and Technology
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• v.42 no.4
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• pp.481-487
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• 2010

The nutritional components, antioxidant, and neuroprotective effects of water and a 50% methanol extract from litchi fruit pericarp were investigated. The most abundant mineral, amino acid, and fatty acid were K, proline, and palmitic acid, respectively. In addition, the total water phenolics and 50% methanol extracts were 8.02 and 12.28 mg/g, respectively. The DPPH, ABTS radical scavenging activities and ferric reducing antioxidant power of the water and 50% methanol extracts showed dose-dependent antioxidant activity. In a cell viability assay using MTT, almost all extracts showed a protective effect against $H_2O_2$-induced neurotoxicity, and lactate dehydrogenase leakage was also inhibited by the pericarp extracts. In particular, the 50% methanol extract showed a higher cell membrane protective effect than the water extract at the highest concentration. Consequently, these data suggest that litchi fruit pericarp can be utilized as an effective and safe functional food substances for natural antioxidants and may reduce the risk of neurodegenerative disorders.

• Management & Information Systems Review
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• v.35 no.2
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• pp.99-118
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• 2016

With the development of Internet and popularization of smartphones over recent years, social network services are experiencing rapid growth. On top of this, smartphone gaming market is showing a rapid growth and the use of mobile social games is on the significant rise. The occurrence of game data manipulation targeting these services and personal information leakage is highlighting the importance of social gaming security. This study is intended to propose development plans effective and efficient in social game services by figuring out factors putting effects on security dependent behavior of social game users in Korea and carrying out a practical study on the casual relationship between factors influencing security dependent behavior through recognized behavioral control and attitudes for privacy infringement of these factors. To do this, proposed was a study model in which the HBM(Health Belief Model) allowing the social game user to influence security dependent behavior was expanded and applied as a major variable. To verify the study model of this study practically, a survey was conducted among university students in Seoul-based K University and S University who had experienced using social game services. According to the study findings, firstly, the perceived seriousness turned out to provide positive influence to trust. But, the perceived seriousness turned out not to put positive effects on self-efficacy. Secondly, the perceived probability turned out not to put positive effects on self-efficacy and trust. Thirdly, the perceived gain turned out to put positive effects on self-efficacy and trust. Fourthly, the perceived disorder turned out not to put positive effects on self-efficacy and trust. Fifthly, self-efficacy turned out to put positive effects on trust. But, self-efficacy turned out not to put positive effects on security dependent behavior. Sixthly, trust turned out not to put positive effects on security dependent behavior. This study is intended to make a strategic proposal so that social game users can raise awareness of their level of security perception and security willingness through this.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.16 no.2
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• pp.183-193
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• 2018

Currently, the Korea Atomic Energy Research Institute (KAERI) is planning to build the Ki-Jang Research Reactor (KJRR) in Ki-Jang, Busan. It is important to safely dispose of low-level radioactive waste from the operation of the reactor. The most efficient way to treat radioactive waste is cement solidification. For a radioactive waste disposal facility, cement solidification is performed based on specific waste acceptance criteria such as compressive strength, free-standing water, immersion and leaching tests. Above all, the leaching test is important to final disposal. The leakage of radioactive waste such as $^{137}Cs$ causes not only regional problems but also serious global ones. The cement solidification method is simple, and cheaper than other solidification methods, but has a lower leaching resistance. Thus, this study was focused on the development of cement solidification for an enhancement of cesium leaching resistance. We used Zeolite and Loess to improve the cesium leaching resistance of KJRR cement solidification containing simulated KJRR liquid waste. Based on an SEM-EDS spectrum analysis, we confirmed that Zeolite and Loess successfully isolated KJRR cement solidification. A leaching test was carried out according to the ANS 16.1 test method. The ANS 16.1 test is performed to analyze cesium ion concentration in leachate of KJRR cement for 90 days. Thus, a leaching test was carried out using simulated KJRR liquid waste containing $3000mg{\cdot}L^{-1}$ of cesium for 90 days. KJRR cement solidification with Zeolite and Loess led to cesium leaching resistance values that were 27.90% and 21.08% higher than the control values. In addition, in several tests such as free-standing water, compressive strength, immersion, and leaching tests, all KJRR cement solidification met the waste acceptance or satisfied the waste acceptance criteria for final disposal.

• Journal of Soil and Groundwater Environment
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• v.14 no.4
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• pp.33-44
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• 2009

Water curtain of an underground LPG storage cavern is a facility to prevent leakage of high pressure gases, for which groundwater should flow freely towards the cavern and groundwater level also must be stably maintained. In this study, in order to evaluate qualities of seepage water and surrounding groundwater of an underground LPG storage cavern in Yeosu, 4 rounds of samplings, field measurements and laboratory analyses (February, May, August, October of 2007) were conducted. According to field measurements, pH was weak acidic to neutral but it gradually increased with time. Electrical conductivity (EC) of groundwater near a salt stack showed very high values between 10.47 and 38.50 mS/cm. Dissolved oxygen (DO) showed a very wide range of 0.20~8.74 mg/L and a mean of oxidation-reduction potential (ORP) was 159 mV, which indicated an oxidized condition. Levels of $Fe^{2+}$ and $Mn^{2+}$ were mostly less than 3 mg/L. All of seepage waters showed a Na-Cl type while only groundwater near the salt stack showed a Na-Cl type with a high total dissolved solid. The other groundwaters exhibited typical $Ca-HCO_3$ types. Levels of aerobic bacteria were mostly very high (573-39,520 CFU/mL). Based on the analyses of these hydrochemistry and biological characteristics, it is concluded that there are no particular problems in groundwater and seepage water, which not causing a trouble in the cavern operation. However, both for control of bio-clogging and for sustainable operation of the water curtain system, a regular hydrochemical and microbiological monitoring is required for the seepage water and surrounding groundwater.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.15 no.1
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• pp.8-15
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• 2010

An experiment was conducted to evaluate the biologically adverse effect of increased carbon dioxide in seawater on marine bacteria, Vibrio fischeri. We measured the bioluminescence and cell density at every 6 hours for 24 hours of the whole incubation period after exposing test microbes to a range of $CO_2$ concentration such as 380(Control), 1,000, 3,000, 10,000 and 30,000 ppm, respectively. Significant effect on relative luminescence(RLU) of V. fischeri was observed in treatments with $CO_2$ concentration higher than 3,000 ppm at t=12 h. However, the difference of RLU among treatments significantly decreased with the incubation time until t=24 h. Similar trend was observed for the variation of cell density, which was measured as optical density using spectrophotometer. The results showed that a significant relationship between $CO_2$ concentration and bioluminescence of test microbes was observed for the mean time. However, the inhibition of relative bioluminescence and also cell density could be recovered at the concentration levels higher than 3,000 ppm. The dissolved $CO_2$ can be absorbed directly by cell and it can decrease the intracellular pH. Our results implied that microbes might be adversely affected at the initial growing phase by increased $CO_2$. However, they could adapt by increasing ion transport including bicarbonate and then could make their pH back to normal level. Results of this study could be supported to understand the possible influence on marine bacteria by atmospheric increase of $CO_2$ in near future and also by released $CO_2$ during the marine $CO_2$ sequestration activity.