• Journal of the Korean Society of Food Culture
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• v.23 no.6
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• pp.812-819
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• 2008

In this study, we assessed the effects of dietary supplementation with Ecklonia cava on blood glucose, lipid metabolism, and renal oxidative stress in streptozotocin (STZ)-induced diabetic rats. Male Sprague-Dawley rats were divided into a normal rat group fed on a control diet and diabetic rats fed on a control diet or supplemented with powder (15% w/w) or water extract of Ecklonia cava (2.5% w/w). Diabetes was induced by a single injection of STZ (60 mg/kg, ip) in citrate buffer. The animals were fed ad libitum with the experimental diet and water for 5 weeks. Dietary supplementation of Ecklonia cava powder and water extract was shown to reduce blood glucose levels in the diabetic rats, and the water extract was more effective than the powder. Dietary supplementation with Ecklonia cava also reduced LDL cholesterol and increased HDL-cholesterol levels in the diabetic rats. Renal glutathione S-transferase activity was increased in the diabetic rats as compared to the normal rats, but reverted to near control values as the result of dietary supplementation with Ecklonia cava. These results show that Eklonia cava exerts an anti-diabetic effect by improving blood glucose concentrations, LDL/HDL-cholesterol ratios, and antioxidative effects on the kidney in diabetic rats.

• Nuclear Engineering and Technology
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• v.56 no.1
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• pp.257-264
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• 2024

The sodium cooled fast reactor (SFR) is one of the Gen-IV reactors with the most operating experience accumulated. Although the technology level is the most mature among the Gen-IV reactors, there is still a safety problem that has not been solved, which is the sodium-water reaction. Since sodium and water are separated only by a heat transfer tube with a thickness of only a few mm, there is inherently a risk of a sodium-water reaction (SWR) accident in the SFR. In this study, it is attempted to quantitatively evaluate the resistance of SWR accidents by replacing the shell and tube steam generator with printed circuit steam generator (PCSG) as a method to mitigate the SWR accident. To do this, a CATS-S (Compact Accident Tolerance Steam Generator-SWR) facility was designed and built. And for the quantitative evaluation of accident resistance, a methodology for measuring the impingement wastage rate was established. As a result of this research, the impingement wastage rate caused by SWR generated in a PCSG was measured first time. It was confirmed that the impingement wastage phenomenon was suppressed in the PCSG, and the accident resistance was higher than that of the SWR through comparison with the experimental results performed in the existing shell and tube steam generator. In conclusion, a PCSG is more resistant to impingement wastage as a result of the SWR accident than existing shell and tube steam generators, and it is estimated that a PCSG can mitigate SWR accidents, an inherent problem of SFR.

• Korean Journal of Environmental Biology
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• v.37 no.2
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• pp.136-143
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• 2019

This study investigates the effect of denitrified biofloc water on changes in the water quality parameters and the physiological characteristics of shrimps. Biofloc rearing water contains a large number of microorganisms and can rapidly stabilize the water quality and energy saving if reusable due to high water temperatures. Rearing water contain floating bacteria with both aerobic and anaerobic bacteria. Therefore, when the carbon source is added in limited air supply, the anaerobic state is activated and the denitrification process is possible. In this study, the denitrification water had the following properties: ammonia (6.9 mg L^-1), nitrite (0.3 mg L^-1), nitrate concentration (9.2 mg L^-1), high pH (8.42) and alkalinity (590 mg L^-1). The experimental group consisted of seawater (SW, control), a mixture of Seawater and denitrified biofloc water (DNW) in the ratio of 3:1, 1:1 and DNW only. All experiments were done in triplicate. As a result, the survival rate never changed even when 100% of the denitrification water was utilized. However, a body fluid analysis showed that creatine and BUN were increased due to index of stress and the tissue damage resulting from the high denitrified water content. Body fluid ions (Na⁺, K⁺, and Cl^-) significantly decreased as the denitrified water content increased. It was recommended that the denitrification water be mixed with a certain ratio (less than 50%) in the future as it may affect the osmotic pressure control in shrimps.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.13-13
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• 2011

The Rio Grande Compact Commission, in collaboration with local water management entities, water users and universities established a three state Rio Grande The Rio Grande Compact Commission, in collaboration with local water management entities, water users and universities established a three state Rio Grande Salinity Management Program. The objectives of the Rio Grande Project Salinity Management Program are to reduce salinity concentrations, loading, and salinity impacts in the Rio Grande basin for the 270 mile river reach from San Acacia, New Mexico to Fort Quitman, Texasto increase usable water supplies for agricultural, urban, and environmental purposes. The focus of this first phase of the program is the development of baseline salinity and hydrologic information and a preliminary assessment of the economic impacts of salinity. An assessment of the economic impacts of salinity in this region was conducted by scientists at Texas A&M University's AgriLife Research Center at El Paso and New Mexico State University. Economic damages attributable to high salinity of Rio Grandewater were estimated for residential, agricultural, municipal, and industrial uses. The major impact issues addressed were: who is being affected the types of economic impacts the magnitude of economic damages overall and by user category and identification of threshold-effect levels for different types of water use. Salinity concentrations in this 270 mile reach of the river typically range from 480 ppm to 1,200 ppm, but can exceed 3,000 ppm in the lower section of this reach. Economic impacts include reductions in agricultural yields, reduced water appliance life, equipment replacement costs, and increased water supply costs. This preliminary economic assessment indicates annual damages of $10.5 million from increased water salinity. Under current water uses, municipal and industrial uses account for 75% of the total estimated impacts. However, agricultural impacts are based on current crop pattern yield reductions and, salinity leaching requirements and do not account for the impacts of reduced revenue from having to grow salinity tolerant, lower value crops. Actual damages are anticipated to be significantly higher with the inclusion of these additional agricultural impacts plus the future impacts from the growing population in the region. A more comprehensive economic analysis is planned for the second phase of this program. Results of the economic analysis are being used to determine the feasiblity of salinity control alternatives and what salinity reduction control measures will be pursued.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.3
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• pp.223-231
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• 1994

To investigate effects of water stress on leaf water potential, nitrate reductase activity and abscisic acid content, Paldalkong, Saealkong and Danyeobkong were subjected to water stress by polyethyene glycol(PEG, MW=6,000) in the water culture and withholding irrigation in soil culture. Leaf water potential and nitrate reductase activity decreased with increaseing of PEG concentration in the water culture. These were higher at 3rd and 5th leaf stage than at 1st leaf stage. Leaf water potential showed no significant differance among the varieties, but nitrate redutase activity was higher in Paldalkong than in Saealkong and Danyeobkong. Leaf water potential and nitrate reductase activity decreased approximately 2.2 times (-1.67 MPa/-0.75MPa) and 47%(3.1${\mu}$ mole nitrite/g.DW/hour/15.9${\mu}$ mole nitrite/g.DW/hour) to control, respectively, after 3 days from water stress treatment in the soil culture. According to increasing PEG concentration, abscisic acid content increased in the water culture and was higher at 5th leaf stage than at 1st and 3rd leaf stage. Paldalkong showed the highest abscisic acid content. Abscisic acid content increased approximately 1.7 times (9.9nmole/g.DW/5.7nmole/g.DW) compared to the control after 3 days from water stress treatment in the soil culture.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.21 no.2
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• pp.126-141
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• 2008

Objective : This clinical research was conducted to test patients with Atopic Dermatitis by external application with Yeongyuseungmatang in cosmetics. Methods : We gave scores to 33 patients who visited the Dept. of Oriental Medical Opthalmology & Otolaryngology & Dermatology of Semyung Jecheon Oriental Medical Hospital from April 17th, 2008 to June 12th. Seventeen patients were treated with Yeongyuseungmatang(Experimental group) and sixteen patients were treated with Atopico skin care cream(Control group) for 4weeks. We observed change of total IgE, eosinophil count, Skin Temperature, Transepidermal Water Loss(TEWL), Skin Hydration and Skin pH. Also Clinic Index of Atopic Dermatitis(SCORAD Index) and global assesment of efficacy were used to evaluate the effects of Yeongyuseungmatang. Statistical analysis was performed by using frequency analysis and descriptive analysis. Statistical significance was achieved if the probability was less than 5%(p<0.05). Results : 1. After 4 weeks of external application treatment, SCORAD Index in Yeongyuseungmatang was significant statistically decreased compared with control group. 2. After 4 weeks of external application treatment, eosinophil count in Yeongyuseungmatang was significant statistically decreased compared with control group but total IgE was very increased both Yeongyuseungmatang and control group. 3. Statistically, Yeongyuseungmatang and control group didn't showed significant effect on Skin Temperature was measured by Thermometer SM815. 4. Transepidermal Water Loss(TEWL) in Yeongyuseungmatang was significant statistically decreased compared with control group measured by Tewameter TM300. 5. Skin Hydration in Yeongyuseungmatang was significant statistically increased compared with control group measured by Corneometer CM825. 6. Statistically, Yeongyuseungmatang and control group didn't showed significant effect on Skin pH was measured by Skin-pH-Meter PH905. 7. After 4 weeks of external application treatment, Yeongyuseungmatang showed significant effect on global assesment of efficacy. Conclusion : Considering the above results, we can speculate that cosmetics with Yeongyuseungmatang has some therapeutical effects in mitigating the symptoms of atopic dermatitis.

• Journal of Acupuncture Research
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• v.35 no.1
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• pp.28-36
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• 2018

Background: This study investigated the effects of acupuncture at Sobu (HT8) and Haenggan (LR2) on scopolamine-induced, cognitively impaired rats. Methods: Scopolamine-treated Sprague-Dawley rats were divided into 6 groups; normal, control, HT8, LR2, HT8 + LR2 and sham group. Cognitive impairment was induced by scopolamine, in control, and then in HT8, LR2, HT8 + LR2 and sham groups. Acupuncture treatment was performed at HT8, LR2, HT8 + LR2, and a random acupoint, respectively, every other day for 2 weeks. After each treatment, behavior change was observed and the rats were sacrificed. The change in brain-derived neurotrophic factor, glutathione peroxidase, and superoxide dismutase activity was evaluated by polymerase chain reaction. Results: Latency time to target in Morris Water-Maze test for the HT8 + LR2 group showed a significant decrease compared with control (p<0.05). Target crossing times and time zone ratios in Morris Water-Maze test for HT8 + LR2 group showed a significant increase compared with control (p<0.01). In the Y-Maze test the HT8 + LR2 group showed a significant increase compared with control (p<0.05). Brain-derived neurotrophic factor, glutathione peroxidase, and superoxide dismutase, in the HT8 + LR2 group, showed a significantly increased level compared with control (p<0.05). Neural activity of acetylcholine esterase in HT8 + LR2 group showed a significant decrease compared with the control group (p<0.01), choline acetyltransferase activity in the HT8 + LR2 group showed a significant increase compared with control (p<0.05). Conclusion: Acupuncture at HT8 + LR2 restored scopolamine-induced cognitive impairment, suggesting acupuncture could be an alternative to improve cognitive function.

• Korean Journal of Agricultural Science
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• v.47 no.4
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• pp.803-814
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• 2020

Managing erosion control dams requires the annual average sediment yield to determine their storage capacity and time to full sediment-fill and dredging. The GeoWEPP (Geo-spatial interface for Water Erosion Prediction Project) model can predict the annual average sediment yield from various land uses and vegetation covers at a watershed scale. This study assessed the GeoWEPP to determine the annual average sediment yield for managing erosion control dams by applying it to five erosion control dams and comparing the results with field observations using ground-based LiDAR (light detection and ranging). The modeling results showed some differences with the observed sediment yields. Therefore, GeoWEPP is not recommended to determine the annual average sediment yield for erosion control dams. Moreover, when using the GeoWEPP, the following is recommended :1) use the US WEPP climate files with similar latitude, elevation and precipitation modified with monthly average climate data in Korea and 2) use soil files based on forest soil maps in Korea. These methods resulted in GeoWEPP predictions and field observations of 0 and 63.3 Mg·yr-1 for the Gangneung, 142.3 and 331.2 Mg·yr-1 for the Bonghwa landslide, 102.0 and 107.8 Mg·yr-1 for the Bonghwa control, 294.7 and 115.0 Mg·yr-1 for the Chilgok forest fire, and 0 and 15.0 Mg·yr-1 for the Chilgok control watersheds. Application of the GeoWEPP in Korea requires 1) building a climate database fit for the WEPP using the meteorological data from Korea and 2) performing further studies on soil and streamside erosion to determine accurate parameter values for Korea.

• Journal of Korean Society on Water Environment
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• v.24 no.4
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• pp.415-422
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• 2008

Drinking water treatment is enhanced by coagulant dosages and chlorine injection because of pH increase in raw water in droughty seasons such as spring and fall. But water quality deterioration is occurred by increase in residual aluminium and disinfection by-products. Coagulation process can be used to control natural organic matter (NOM) during water treatment. The effect of coagulation process appeared to depend on the pH of water rather than coagulant dosages. In this study, for water treatment in high pH season $H_2SO_4$ was applied for pH adjustment at full scale. Before and after pH adjustment by $H_2SO_4$ injection, water quality of drinking water was evaluate. In the result of investigation of total organic carbon (TOC) removal in high pH season, TOC was removed approximately 30~40%, which showed decrease in water treatment efficiency. Also, it is increased both particle numbers and residual Al concentration in the water. After $H_2SO_4$ injection for adjustment to pH<7.5 in settled water, treated water turbidity decreased in 0.047 NTU from 0.059 NTU, and particle numbers of filtered water decreased in 20/mL from 90/mL. On the other side, TOC removal efficiency increased in approximately 10% after adjustment of pH. In the result of decrease in pH in raw water through more coagulants and prechlorine without $H_2SO_4$ injection, trihalomethanes (THMs) concentration increased in $16{\mu}g/L$ from $8{\mu}g/L$.

• The Korean Journal of Food And Nutrition
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• v.25 no.1
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• pp.196-204
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• 2012

This research focused on the effects of adding Hizikia fusiforme to Jeolpyun. We were able to demonstrate in this study that Jeolpyun after the addition of Hizikia fusiforme had the potential to become a functional food. Jeolpyun with 0, 2, 4, 6, and 8% of Hizikia fusiforme was analyzed by water content, color, sensory and textural characteristics immediately after production and one day later. The five different types of Jeolpyun did not show any significant differences in water content. However, all the Jeolpyun with Hizikia fusiforme showed slightly higher water retention ratio than the control after storage. As the result of Hunter's color values, lightness decreased significantly as the amount of Hizikia fusiforme increased. Redness increased in the Jeolpyun with Hizikia fusiforme compared with the control. Yellowness was highest in the Jeolpyun with 2% of Hizikia fusiforme and decreased with an increase in its content. In the textural analysis, hardness, chewiness, adhesiveness and gumminess of Jeolpyun with 2% and 4% of Hizikia fusiforme were similar to those of the control, whereas springiness of Jeolpyun with 2%, 4% and 6% of Hizikia fusiforme were similar to that of the control group. Cohesiveness significantly decreased as the amount of Hizikia fusiforme increased. When the Jeolpyun was preserved for one day, all five Jeolpyun showed significant increases in hardness, gumminess and chewiness. However, their adhesiveness significantly decreased. Cohesiveness decreased in all Jeolpyun except for the 8% Jeolpyun. In sensory evaluation, color and aroma became stronger as the content of Hijikia fuziforme increased, and 2% Jeolpyun showed similar hardness with the control. Jeolpyun with Hijikia fuziforme showed no difference in cohesiveness with the control, but the adhesiveness showed a little increase when compared to the control. The overall acceptability of 2% Jeolpyun showed slightly higher than control. After one day of storage, Jeolpyun with 2% of Hijikia fuziforme also showed the highest overall acceptability. And the overall acceptability showed the biggest decrease in the control group. Overall acceptability showed strong negative correlation with color, aroma and hardness, and showed strong positive correlation with cohesiveness and adhesiveness. After one day of storage, overall acceptability showed a decrease in correlation with color and smell and an increase in correlation with cohesiveness, compared to before storage. Results of multiple regression analysis showed that hardness had the biggest influence(-) on the overall acceptability of Jeolpyun, aroma and cohesiveness ranked second(-) and third(+) respectively. After one day of storage, cohesiveness had the biggest influence on the overall acceptability of Jeolpyun. Color and adhesiveness ranked second(-) and third(+) respectively. It can be seen that different factors influence overall acceptability of Jeolpyun after storage.