• Journal of Korean Neurosurgical Society
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• v.54 no.2
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• pp.93-99
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• 2013

Objective : Neurologic complications during carotid artery stenting (CAS) are usually associated with distal embolic event. These embolic incident during CAS are highly associated with the carotid plaque instability. The current study was undertaken to identify the angiographic characteristics of carotid plaque vulnerability, which was represented as filling defect in the cerebral protection filters during CAS. Methods : A total of 107 patients underwent CAS with use of a distal protection filter. Angiographic carotid plaque surface morphology was classified as smooth, irregular, and ulcerated. To determine predictable factors of filling defect in the protection filters, 11 variables were retrospectively analyzed which might influence filling defect in the protection filters during CAS. Results : Filling defects during CAS were presented in the 33 cerebral protection filters. In multivariate analysis, angiographic ulceration [odds ratio (OR), 6.60; 95% confidence interval (CI) : 2.24, 19.4; p=0.001], higher stenosis degree (OR, 1.06; 95% CI : 1.00, 1.12; p=0.039), and coexistent thrombus (OR, 7.58; 95% CI : 1.69, 34.05; p=0.08) were highly associated with filling defect in the cerebral protection devices during CAS. Among several variables, angiographic surface ulceration was the only significant factor associated with flow stagnation during CAS (OR, 4.11; 95% CI : 1.33, 12.72; p=0.014). Conclusion : Plaque surface morphology on carotid angiography can be a highly sensitive marker of plaque instability during CAS. The independent risk factors for filling defect in the filter devices during CAS were plaque ulceration, stenosis degree, and coexistent thrombus.

• Journal of Korea Water Resources Association
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• v.47 no.12
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• pp.1121-1134
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• 2014

The distributed watershed model of rainfall-runoff-soil erosion-sedimen transport was constructed for the Naesung Stream Watershed with high potentiality and risk of sediments produced by soil erosion. The sensitivity analyses of roughness coefficient and hydraulic conductivity which affected the modeling results of runoff and sediment concentration were performed in this study. As a result, the change of the roughness coefficient for the forest area from 0.4 to 0.45 did not affect the change in runoff and stream discharge and the average value and range of sediment concentration were also insignificantly increased with few difference. As a result of the sensitivity analysis of the hydraulic conductivity, the total amount of runoff and maximum runoff were gradually increased as the hydraulic conductivity was reduced. In the case of sediment concentration modeling, the average and the range of sediment concentration for all stations were increased as the hydraulic conductivity was decreased. For the Hyangseok Station, in case of the hydraulic conductivity reduced by 50%, the simulation result of sediment concentration was most similar to the estimated value by the sediment rating curve.

• Journal of Wetlands Research
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• v.13 no.1
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• pp.25-33
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• 2011

Climate change is the variation of long term weather pattern based on statistical diversities in terms of natural and artificial factors. Recent numerous extreme weather phenomena have increasingly obtained people's awareness of climate change. Since water resources field especially has higher vulnerability caused by climate variation, the major part of future preparation should be focused on risk minimization of water resources. However, in reality validation of water resources vulnerability is not well built up. For this research, Delphi Method was applied to evaluate middle/small size rivers in Korea with respect to the degree of vulnerability due to the climate change. Delphi Survey is based on iterative, anonymous characteristics with experts' opinion sharing on the given issues. For this study, three iterative surveys were operated for the degree of vulnerability. First round was for selecting vulnerability indicators in terms of the magnitude of total score, and second and third rounds were for collecting experts' idea with opinion convergence. Per the variance of standard deviation of 2nd and 3rd surveys divergence, we clearly see the achievement of opinion agreement. For the future study, we may need to find an applicable field using delphi indicators with various circumstances.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.20-20
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• 2011

The purpose of this research aims to evaluate the emergence of new business mode in the Chinese water market since the mid-2000s - Transfer-Operate-Transfer(TOT) Projects. The study pays special attention to the case of the Hefei Wangxiaoying Wastewater Treatment TOT Project, which was awarded to the consortium of Berlin Water International and its Chinese partner in late 2004. The consortium secured an exclusive operating right for 23 years on the basis of a TOT scheme and would take responsibility of all the profits and losses in the operation of the plant. The total investment for the transfer amounted to RMB 491 million(US$70 million). The price was more than 288% of the original value, RMB 170 million (US$24 million). The project can be regarded as a successful case because of the following three causes. First, the Hefei government followed a series of standardized procedures in the international bidding, which ignited best-performed international players' competition for the project. Second, the project will bring in cutting-edge operation skills and management know-how. Third, the government succeeded in raising public asset values, and thanks to this, the government is able to consider other similar projects not only in the water sector but also other sectors in public utility services. Nevertheless, Berlin Water's point of view, there are several challenges. First, the company took a risk to pay such a large amount of cash to the Hefei government. Although such premium can be recouped in the operation period of 23 years, whether or not the company would be able to recover the initial investment and realize profits is in question due to an uncertainty of socio-political circumstances in China. Second, Berlin Water should expect a steep rise of water tariffs over the contract period in order to get the investment back. Water pricing is still a sensible matter to Chinese authorities, and therefore, it is uncertain if such rise of water tariffs would be possible. Third, the TOT mode leads to creation of a large amount of cash to government officials, which might have caused corruption between those who are involved in TOT deals. Then, the final contract fee would soar, which often results in the burden of normal customers. As discussed, the TOT mode has drawn much attention of foreign investors as a new alternative to enter into the Chinese water market. But it is important to note that foreign investors should be aware of possible risks in water TOT projects, which reflects some features of the Chinese political economy landscape and social norms. The Hefei case indicates that benefits can overshadow risks in TOT projects, which will continue to attract foreign investors that are dedicated to establishing their strongholds in the Chinese water market.

• Herbal Formula Science
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• v.16 no.2
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• pp.133-144
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• 2008

Recently, people are becoming fatter in most parts of the world. Obesity is regarded as an important risk factor to adversely affect the health of humans, associated with hypertension, hyperlipidemia, diabetes, and cardiovascular diseases. In the present study, therefore, we tested the short time efficiency and safety of Bangpoongtongsungsan as a drug to decrease body weight in subjects with obesity. A total 48 volunteers (24 man, 24 woman) with body mass index (BMI : weight in kg divided by square of height in meters) of $23㎏/m^2$ participated in clinical study for 12 weeks, from 2008, March 01 to 2008, Jun 30. The subjects was received a dietary supplement of 12 pieces hard capsules per day (4 pieces in one, 3 times in a day) during the clinical study. At the end of clinical study, body weight of subjects was significantly decreased from $72.21{\pm}11.44\;kg$ to $70.53{\pm}11.67\;kg$ (p<0.05). Waist circumferences of subjects were reduced $91.58{\pm}6.43\;cm$ to $85.25{\pm}7.70\;cm$ (p<0.05). Also, a BMI of subjects was significantly decreased $26.07{\pm}2.35\;kg/m^2$ to $25.63{\pm}2.63\;kg/m^2$ (p<0.05). Particularly, a decrease in body weight, waist circumferences, and BMI was more significant in woman than man. But, other biochemical levels including lipid and glucose in plasma had no changes at the end of clinical study. In conclusion, administration of Bangpoongtongsungsan in subjects with high body weight fat could inhibit obesity associated with a decrease in body weight, waist circumferences, and BMI.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.3
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• pp.464-468
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• 2003

The antihypertensive and cholesterol- lowering effects of Monascus koji (M. koji) prepared with Monascus ruber IFO32318 were examined in spontaneously hypertensive rats (SHR). Control was fed a normal diet and groups I, II or III were fed diets containing 0.03%, 0.1% or 0.3% M. koji for 8 weeks, respectively. After 8 weeks, all animals were fed normal diets in the following 2 weeks. The blood pressure of rats fed M. koji added diets were significantly attenuated as compared with control and the diet containing high concentration of M. koji had a tendency of stronger antihypertensive effect. These differences lasted throughout the experimental period when they were fed experimental diet. For 2 weeks after the 8 weeks of experimental diet all groups were fed the same normal diet and the differences of blood pressure caused by M. koji disappeared. In rats fed the M. koji added diet, the serum total cholesterol (TC), HDL cholesterol (HDL-C), LDL cholesterol (LDL-C) were not differed compared with control, but VLDL cholesterol (VLDL-C) was significantly lowered. M koji also significantly decreased serum risk factors, both TC/HDL-C ratio and non HDL-C/HDL-C ratio. Consequently, it is suggested that M. koji may play an important role to attenuate hypertension and to improve serum lipid Profiles.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.8
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• pp.1199-1208
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• 2005

Abatement of greenhouse gas emitted from ruminants and promotion of biogas energy from animal effluent were comprehensively examined in each anaerobic fermentation reactor and animal experiments. Moreover, the energy conversion efficiency of biomass energy to power generation were evaluated with a gas engine generator or proton exchange membrane fuel cell (PEMFC). To mitigate safely rumen methanogenesis with nutritional manipulation the suppressing effects of some strains of lactic acid bacteria and yeast, bacteriocin, $\beta$1-4 galactooligosaccharide, plant extracts (Yucca schidigera and Quillaja saponarea), L-cysteine and/or nitrate on rumen methane emission were compared with antibiotics. For in vitro trials, cumulative methane production was evaluated using the continuous fermented gas qualification system inoculated with the strained rumen fluid from rumen fistulated Holstein cows. For in vivo, four sequential ventilated head cages equipped with a fully automated gas analyzing system were used to examine the manipulating effects of $\beta$1-4 galactooligosaccharide, lactic acid bacteria (Leuconostoc mesenteroides subsp. mesenteroides), yeast (Trichosporon serticeum), nisin and Yucca schidigera and/or nitrate on rumen methanogenesis. Furthermore, biogas energy recycled from animal effluent was evaluated with anaerobic bioreactors. Utilization of recycled energy as fuel for a co-generator and fuel cell was tested in the thermophilic biogas plant system. From the results of in vitro and in vivo trials, nitrate was shown to be a strong methane suppressor, although nitrate per se is hazardous. L-cysteine could remove this risk. $\beta$1-4 galactooligosaccharide, Candida kefyr, nisin, Yucca schidigera and Quillaja saponarea are thought to possibly control methanogenesis in the rumen. It is possible to simulate the available energy recycled through animal effluent from feed energy resources by making total energy balance sheets of the process from feed energy to recycled energy.

• Environmental Analysis Health and Toxicology
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• v.5 no.3_4
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• pp.19-28
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• 1990

Nitroarenes are ubiquitous environmental pollutants displaying potent mutagenicity in bacteria and carcinogenicity in mammal. In this study, the concentration of nitroarenes in coarse and fine particles and mutagenicity of POC$\_$N/ fraction was investigated in suspended particulates at the Shinchon and Bulkwang area of Seoul. The suspended particulates were collected bimonthly by a high volume cascade impactor air sampler from July 1987 to May 1988. Extractable organic matter was obtained by ultrasonic extraction on diethly ether/cyclohexane (8/2, v/v). Neutral fraction was obtained by liquid-liquid extraction. Polar neutral organic compounds (POC$\_$N/) was fractionated by thin-layer chromatography. Finally, the concentrations of nitroarenes in POC$\_$N/ fraction were measured and determined by capillary gas chromatography. Direct and indirect mutagenicity of POC$\_$N/ fraction were measured using Salmonella typhimurium TA 98. The result were as follows: 1) Major nitroarenes at the Shinchon area was 1-nitropyrene and at the Bulkwang area it was 2,7-dinitro-9-fluorenone during the year. 2) Average concentration of total nitroarenes measured was 67.26 ng/m$^3$in fine particles which was 1,3 folds higher that in coarse particle (52.30 ng/m$^3$). 3) Annual pattern of nitroarenes concentrations revealed that concentration during heating season (Feb., Jan., Mar.) was 2.2 folds higher than that in non heating season (May, Jul., Sep.). Concentration of each season has 157.68 ng/m$^3$and 80.39 ng/m$^3$. 4) The mutagenic activity of POC$\_$N/ fraction from fine particles was higher compared to that of coarse particles and was increased when metabolically activated, with 59 mixture. Mutagenicities, Metabolically activated, were significantly different between Shinchon and Bulkwang area, 322.8 rev/250 $\mu\textrm{g}$/plate and 286.8 rev/250 $\mu\textrm{g}$/plate, respectively. 5) Annual pattern of mutagenicity of POC$\_$N/ fraction revealed that mutagenicity during the heating season was 1.7 folds higher at Shinchon area and 1.2 folds higher at Bulkwang than during the non heating season. The variable contents and levels of nitroarenes in suspended particulates may affect human health significantly. Further studies such as risk assessment should be conducted on the basis of these kind of studies.

• Journal of Animal Science and Technology
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• v.47 no.2
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• pp.177-186
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• 2005

Xenotransplantation may help to overcome the critical shortage of human tissues and organs for human transplantation, Swine represents an ideal source of such organs owing to their anatomical and physiological similarities to human besides their plentiful supply, However, the use of organs across the species barrier may be associated with the risk of transmission of pathogens, specially porcine endogenous retroviruses (PERVs).• Although most of these potential pathogens could be eliminated by pathogen-free breeding, PERVs are not eliminated by this treatment. PERVs are integrated into the genome of all pigs and produced by normal pig cells and infect human cells. They belong to gamma retroviruses and are of three classes viruses: A, B and C. In the present study, PCR based cloning was performed with chromosomal DNA extracted from pigs from domestic pigs in Korea. Amplified PCR fragments of about 1.5 Kb, covering the partial env gene, were cloned into pCR2.l-TOPO vectors and sequenced. A total of 91 env clones were obtained from domestic pigs, Berkshire, Duroc, Landrace and Yorkshire in Korea. Phylogenetic analysis of these genes revealed the presence of only PERV class A and B in the proportion of 58 % and 42 %, respectively. Among these, 28 clones had the correct open reading frame: 18 clones in class A and 10 clones in class B. Since both these PERV classes are polytropic and have the capacity to infect human cells, our data suggest that proviral PERVs have the potential to generate infectious viruses during or after xenotransplantation in human.

• Clinical and Experimental Pediatrics
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• v.54 no.6
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• pp.253-259
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• 2011

Purpose: Long-term survivors of childhood cancer appear to have an increased risk for the metabolic syndrome, subsequent type 2 diabetes and cardiovascular disease in adulthood compared to healthy children. The purpose of this study was to investigate the frequency of the metabolic syndrome and associated factors in childhood cancer survivors at a single center in Korea. Methods: We performed a retrospective review of medical records of 98 childhood cancer survivors who were diagnosed and completed anticancer treatment at Samsung Medical Center, Seoul, Korea between Jan. 1996 and Dec. 2007. Parameters of metabolic syndrome were evaluated between Jan. 2008 and Dec. 2009. Clinical and biochemical findings including body fat percentage were analyzed. Results: A total of 19 (19.4%) patients had the metabolic syndrome. The median body fat percentage was 31.5%. The body mass index and waist circumference were positively correlated with the cranial irradiation dose (r=0.38, P<0.001 and r=0.44, P<0.00, respectively). Sixty-one (62.2%) patients had at least one abnormal lipid value. The triglyceride showed significant positive correlation with the body fat percentage (r=0.26, P=0.03). The high density lipoprotein cholesterol showed significant negative correlation with the percent body fat (r=- 0.26, P=0.03). Conclusion: Childhood cancer survivors should have thorough metabolic evaluation including measurement of body fat percentage even if they are not obese. A better understanding of the determinants of the metabolic syndrome during adolescence might provide preventive interventions for improving health outcomes in adulthood.