• YAKHAK HOEJI
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• v.57 no.6
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• pp.383-387
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• 2013

In the present study, we determined the antifungal effect of obacunone isolated from Phellodendri Cortex against Candida ablicans, a pathogenic fungus. The antifungal effect was analyzed by an in-vitro susceptibility test and in a murine model of disseminated candidiasis. Possible mechanism of the antifungal activity was also examined. Analyses of data resulting from the susceptibility test revealed that the compound inhibited C. albicans growth. At 25 ${\mu}g$ obacunone/ml, there was app. 45% reduction of CFUs (colony forming units) as compared to obacunone-untreated C. albicans yeast cells (P<0.01). In the murine model of disseminated candidiasis due to C. albicans, obacunone enhanced resistance of mice against disseminated candidiasis. During an entire period of 30-day observation, control animals all died within 14 days, whereas 60% of obacunone-treated mice survived (P<0.05). In addition, obacunone inhibited the hyphal production, a major virulence factor of C. albicans, from the blastoconidial form. Thus, obacunone appears to have antifungal activity for C. albicans infection. This may possibly be mediated by the blockage of hyphal production.

• Advances in concrete construction
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• v.14 no.2
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• pp.115-130
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• 2022

This paper presents an application of the maturation effect on the strength of high-strength concrete which is produced with different origin aggregates. While investigating the maturation effect on HSC 384 specimens were prepared with 22 different origin aggregates. These prepared specimens were subjected to the standard compressive tests which were applied after curing for 2, 7, 28, and 56 days under appropriate conditions. The test results revealed that bright surface-low adherence behavior is valid in normal strength concretes, but is not as effective as expected in high-strength concretes. The application of artificial neural networks (ANNs) to predict 2, 7, 28, and 56 day compressive strength of HSC is also investigated in this paper. An ANN model is built, trained, and tested using the available test data gathered from experimental studies. The ANN model is found to predict 2, 7, 28, and 56 days of compressive strength of high-strength concrete well within the ranges of the input parameters considered. These comparisons show that ANNs have strong potential as a feasible tool for predicting the compressive strength of high-strength concrete within the range of the input parameters considered.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.6
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• pp.1762-1768
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• 2004

The Korean formula medicine, Gami-Yukmi-Jihwang-Tang (GYJT) has been used for growing slowly, short of stature, incomplete development, fatigue, weak child, growing pain of child. However, it is still unclear how GYJT has an effect on experimental models. In the present study, the author investigated the immune-enhancing effect of GYJT. Forced swimming test (FST) was performed as a model of activity test in mice and measured blood urea nitrogen (BUN), aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactic dehydrogenase (LDH), glucose (Glc) and total protein (TP) in the serum. GYJT (1, 0.1 and 0.01 g/㎏) were orally administered to mice, once per day for 7 days using a feeding atraumatic needle. After 3 days, on FST, the immobility time was significantly decreased in the GYJT (0.01g/㎏/day)-fed group (120.75±5.71s) in comparison with the saline-fed group (153.80±10.74s). After 7 days, the immobility time was significantly decreased in the GYJT (0.1 and 0.01g/㎏/day)-fed group (125.67±5.36s and 107.67±3.71s) in comparison with the saline-fed group (167.67±12.99s). In addition, the contents of BUN and Glc in the blood serum were significantly decreased and the contents of AST, ALT and LDH were also decreased in the GYJT (1g/㎏/day)-fed group. However, the content of TP was not changed. The present results suggest that GYJT may be useful for the anti-fatigue and immune-enhancing agent. Also, the author investigated the effect of GYJT on the production of cytokines in human T-cell line, MOLT-4 cells. However, GYJT has not affected the production of IFN­γ, IL-2, IL-4. These results suggest that GYJT has immune-enhancing effect but does not affect T cell-mediated production of cytokines in the immune function improvement.

• Journal of Environmental Science International
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• v.13 no.8
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• pp.733-737
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• 2004

FThe aim of this study was to carry out a preliminary test of the air quality modelling system (HIRES-AIRCHEM) developed at The University of New South Wales, particularly with regard to the forecast ozone distribution. This was achieved by assimilating the New South Wales State Environment Protection Authority (EPA) emissions inventory, consisting of road and non-road sources, and running the system over the Sydney metropolitan area for the four day period 25-28 February 1998. During this period ozone readings exceeded the EPA's goal of 8pphm on several occasions. The model forecasts of ozone distribution verified well with the EPA's ozone readings. This result has important implications for possible future use of the system as a tool for routinely predicting and assessing air quality.

• Journal of the Korean Institute of Landscape Architecture
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• v.22 no.3
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• pp.1-12
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• 1994

This study was carried out to identify destination choice behavior for one-day use recreation areas. Previous positioning study was utilized to select 4 study areas, and the secondary data were used for logit analyses. The Hausamn-McFadden test for IIA was conducted to examine whether conditional logit models are valid methodology for this study. The results revealed that IIA assumption among the study areas was violated; therefore, generalized binomial and generalized multinomial logit models were used in this study. In the binomial logit analysis, 2 to 5 independent variables were included in the models: their $\rho$2 values were from 0.1to 0.323, and accuracy of predictions were from 65.38 to 79.86 percent. In the multinomial logit analysis, 4 independent variables were included in the model: its $\rho$2 value was 0.207, and accuracy of prediction was 45.82 percent. The results showed that the conditional logit should be used with caution because of the IIA assumption. Several suggestions were described, mainly due to utilization of the secondary data for this study.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11a
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• pp.212-215
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• 2003

The aim of this study was to test the air quality modelling system (HIRES-AIRCHEM) of The University of New South Wales particularly with regard to forecast ozone distribution. This was achieved by assimilating the New South Wales State EPA emissions inventory consisting of road and non-road sources and running the system over the Sydney metropolitan area for the four day period 25-28 February 1998. During this period ozone readings exceeded the EPA＇s goal of 80ppb on several occasions. The model forecasts of ozone distribution verified well with the EPA＇s ozone readings. This result has important implications for possible future use of the system as a tool for routinely assessing air quality.

• Journal of Korean Biological Nursing Science
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• v.10 no.2
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• pp.176-183
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• 2008

Purpose: The purpose of this study was to identify the effect of Environmental Enrichment (EE) on improvement of motor function in animal models of Parkinson's Disease. Methods: Male C57BL6 mice weighing 25-30 g, at the age of 12 wks were used in this study. The animals were injected MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridin, 20 mg/kg in saline, i.p.) 4 times a day at every 2 hr, and raised in EE cage for 14 days. On day 14, after behavior test, all mice were sacrificed for immunohistochemistry. All values were expressed as means$\pm$S.E.M. Statistical significance was evaluated using a one way ANOVA followed by Sheffe test. Results: There was a significant difference between the experimental group and the control group in the behavior test. Also EE significantly reduced of TH positive cell loss in Substantia nigra pars compacta as compared to the result of MPTP treatment. Conclusion: Based on these findings, it is reasonable to assume that the environmental enrichment prevents dopaminergic neuronal loss and improves disarrangement of motor function and behavioral disability induced by MPTP.

• The Journal of Engineering Geology
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• v.30 no.3
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• pp.269-278
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• 2020

In this study, the effects of groundwater artificial recharge through vertical wells in the upper small basin are preliminarily evaluated by using field injection test and a 3-D numerical model. The injection rate per well in a model is set to 20, 37.5, 60, and 75 ㎥/day based on the results of field injection test, groundwater levels, and hydraulic conductivities estimated from particle size analysis, and a numerical model using MODFLOW is conducted for 28 cases, which have diverse injection intervals, in order to estimated the changes of groundwater level and water balance after injection. Groundwater level after injection does not show a linear relationship with the injection rate per well, and the cumulative effect of artificial recharge decreases and the timing of maximum water level rise is shortened as the injection interval becomes longer. In four cases of continuous injection with total injection rate of 1,200 ㎥, it is revealed that the recharge effect is analyzed as 36.5~65.3% of the original injection rate. However, it will be more effective if the artificial recharge system combined with underground barrier is introduced for the longer pumping during a long and severe drought. Additionally, it will be possible to build a stable artificial recharge system by an establishment of efficient scenario from recharge to pumping as well as an optimization of recharge facilities.

• Journal of the Korea Organic Resources Recycling Association
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• v.24 no.1
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• pp.21-29
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• 2016

We mix food waste leachate and sewage sludge by the proportion of 1:9, 3:7 and 5:5. It turns out that they produced 233, 298 and 344 $CH_4{\cdot}mL/g{\cdot}VS$ of methane gas. The result suggests that as the mixing rate of food waste leachate rises, the methane gas productions increases as well. And more methane gas is made when co-digesting sewage sludge and food waste leachate based on the mixing ratio, rather than digesting only sewage sludge alone. Modified Gompertz and Exponential Model describe the BMP test results that show how methane gas are produced from organic waste. According to the test, higher the mixing rate of food waste leachate is, higher the methane gas productions is. The mixing ratio of food waste leachate that produces the largest volume of methane gas is 3:7. Modified Gompertz model and Exponential model describe the test results very well. The correlation values($R^2$) that show how the results of model prediction and experiment are close is 0.92 to 0.98.

• The Korean Journal of Food And Nutrition
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• v.29 no.3
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• pp.382-391
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• 2016

The purpose of this experiment was designed to investigate the effects of medicinal herbs (MH) extracts on dementia induced by trimethyltin chloride (TMT) in rats. Six-week-old male Sprague-Dawley rats were randomly divided into five groups; normal group (group 1), control group (group 2), MH extracts group (250, 500 mg/kg) (group 3, group 4) and positive control group (tacrine group, group 5). In the control group to induce dementia, a 2.5 mg/kg of TMT intraperitoneal injection was used for 14 days (1 per day) in the rats. In the MH extracts group 250 mg/kg and 500 mg/kg of MH extracts were medicated in an oral inoculation for 20 days (1 per day). After 30 minutes, a 2.5 mg/kg of TMT intraperitoneal injection, which causes dementia, was used for 14 days (1 per day). In the positive control group (Tacrine group) 10 mg/kg of Tacrine, the dementia treatment, was medicated in an oral inoculation. After 30 mintues, 1 mg/kg of TMT intraperitoneal injection, which causes dementia, was used for 14 days (1 per day). The present author observed the passive avoidance performance test, and memory ability test (Y maze test), the values of MDA, acetlycholinesterase (AchE) activity in the brain and antioxidant enzyme in serum. MH extracts significantly improved memory of AD model rats in the Y-maze test, and also significantly improved memory of AD model rats in the passive avoidance test. MH extracts significantly reduced AChE activity, and significantly increased the SOD level, but not catalase and MDA. From the results above, MH extracts is thought to be effective in the improvement of antioxidant enzymes and memory ability.