• Journal of Korea Water Resources Association
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• v.41 no.2
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• pp.149-162
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• 2008

The Soil and Water Assessment Tool (SWAT) developed by the USDA-Agricultural Research Service for the prediction of land management impact on water, sediment, and agricultural chemical yields in a large-scale basin was applied to Daecheong Reservoir basin to estimate the amount of soil losses from different land uses. The research outcomes provide important indications for reservoir managers and policy makers to search alternative watershed management practices for the mitigation of reservoir turbidity flow problems. After calibrations of key model parameters, SWAT showed fairly good performance by adequately simulating observed annual runoff components and replicating the monthly flow regimes in the basin. The specific soil losses from agricultural farm field, forest, urban area, and paddy field were 33.1, $2.3{\sim}5.4$ depending on the tree types, 1.0, and 0.1 tons/ha/yr, respectively in 2004. It was noticed that about 55.3% of the total annual soil loss is caused by agricultural activities although agricultural land occupies only 10% in the basin. Although the soil erosion assessment approach adopted in this study has some extent of uncertainties due to the lack of detailed information on crop types and management activities, the results at least imply that soil erosion control practices for the vulnerable agricultural farm lands can be one of the most effective alternatives to reduce the impact of turbidity flow in the river basin system.

• Journal of Environmental Impact Assessment
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• v.26 no.6
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• pp.563-573
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• 2017

Coal ash is generated from coal-fired thermal power plants every year. The remaining quantity of coal ash ends up in the landfills except for the recycled portion, and the existing ash pond capacity is limited almost. Currently, the difficulties are faced in building a new ash treatment plant because of the concerns about the environmental impacts of landfills at individual plant facilities. In terms of minimizing the environmental impact, the recycling and effective uses of coal ash are recognized as urgent issues to be challenged. Accordingly, this study examines the obstacles in expanding the recycling of the coal ash in South Korea and proposes solutions based on the case study analysis. The analysis results are as follows: 1) specific recycling guidelines and standards are required to be established in accordance with the contact medium (soil, ground water, surface water and sea water) and the chemical. 2) by providing the recognition environmentally safe in recycling the coal ash, transparency in establishing the planning stages and active communication with the community through promotion and research are essentially needed. 3) practical support system is required to encourage the power plant companies to use the coal ash as beneficial use.

• Applied Biological Chemistry
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• v.34 no.1
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• pp.54-60
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• 1991

Serratia marcescens CK-3, decomposing chitin which is a mar component of cell wall in phyitopathogenic fungi, was isolated from the continuous cropping rhizosphere of pepper and cucumber and its enzymatic property was examined. S. marcescens CK-3 was found tn have an tagonistic effects against, Fusarium axysporum and Rhizoctonia solani and to have complex enzyme system such as chitinase, laminarinase, and proteinase. The preferable composition of the medium for production of chitinase was fond and was as follows : colloidal chitin 1.5%, tryptone 0.5%, glucose 1.0%, peptone 0.2%, $MgSO_4{\cdot}7H_2O\;0.1%,\;K_2HPO_4\;0.1%,\;and\;NaCl\;0.1%$(w/v), pH 6.8. The maximum enzyme production was observed after culture of 72 hours at $30^{\circ}C$ using a medium containing the above chemical composition. The optimal pH and temperature for in vitro activity of chitinase from S. marcescens CK-3 were pH 7.5 and $50^{\circ}C$, respectively. The enzyme activity in-creased by metal ions such as$Ag^+$ and $Mn^{++}$.

• Korean Journal of Ecology and Environment
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• v.42 no.4
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• pp.476-486
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• 2009

Major objective of our study was to introduce initial researches of national long-term ecological monitoring studies on Daechung Reservoir, as one of the representative lentic reservoir ecosystems in Korea. For the long-term ecological research (LTER), we conducted preliminary field monitoring during 2008~2009 and analyzed biological parameters such as phytoplankton, zooplankton, and freshwater fish along with chemical water quality and empirical model analysis. According to phytoplankton surveys, major taxa have varied largely depending on seasons and sites sampled. Overall phytoplankton data showed that cyanophyta dominated in the summer period and diatoms dominated in the winter. In zooplankton analysis, 25 species including 20 rotifers, 3 cladocerans and 2 copepods were collected during the survey. The relative abundance of rotifers (86.5%) was always greater than that of cladocerans (6.3%) or copepods (5.1%). There were distinct spatial and inter-annual changes in the abundance of zooplankton in the reservoir, displaying similar patterns in three sites with the exception of S3 during the study. According to fish surveys, 8 families and 39 species were observed during 2008~2009. The most dominant fish was an exotic species of Lepomis macrochirus (23%), indicating an severe influence of exotic species to the ecosystem. TP averaged $17.9\;{\mu}g\;L^{-1}$ ($6{\sim}80\;{\mu}g\;L^{-1}$), which was judged as a mesotrophy, and showed a distinct longitudinal gradients. TN averaged $1.585\;{\mu}g\;L^{-1}$ during the study and judged as hypereutrophic condition. Unlike TP, TN didn't show any large seasonal and spatial variations. Under the circumstances, nitrogen limitation may not happen in this system, indicating that nitrogen control is not effective in the watershed managements. These data generated in the LTER station will provide key information on long-term biological and water quality changes in relation to global warming and some clues for efficient reservoir ecosystem managements.

• Safety and Health at Work
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• v.4 no.3
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• pp.142-148
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• 2013

Background: To elucidate the relationship between seven occupational dermatoses (ODs) and 20 types of work in Greece. Methods: This was a prevalence epidemiologic study of certain ODs among 4,000 workers employed in 20 types of enterprise, in 104 companies, in 2006-2012, using data from company medical records, questionnaires, occupational medical, and special examinations. The ${\chi}^2$ test was applied to reveal statistically significant relationships between types of enterprises and occurrence of ODs. Results: A high percentage (39.9%) of employees included in the study population suffered from ODs. The highest prevalence rates were noted among hairdressers (of contact dermatitis: 30%), cooks (of contact dermatitis: 29.5%), bitumen workers (of acne: 23.5%), car industry workers (of mechanical injury: 15%), construction workers (of contact urticaria: 29.5%), industrial cleaning workers (of chemical burns: 13%), and farmers (of malignant tumors: 5.5%).We observed several statistical significant correlations between ODs (acute and chronic contact dermatitis, urticaria, mechanical injury, acne, burns, skin cancer) and certain types of enterprises. There was no statistically significant correlation between gender and prevalence of ODs, except for dermatoses caused by mechanical injuries afflicting mainly men [${\chi}^2(1)=13.40$, p < 0.001] and for chronic contact dermatitis [${\chi}^2(1)=5.53$, p=0.019] afflicting mainly women. Conclusion: Prevalence of ODs is high in Greece, contrary to all official reports by the Greek National Institute of Health. There is a need to introduce a nationwide voluntary surveillance system for reporting ODs and to enhance skin protection measures at work.

• Journal of the Korean Applied Science and Technology
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• v.20 no.2
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• pp.101-109
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• 2003

Provitamin $B_5$ liquid crystal ($PVB_5$-LC) was the new emulsion system to enhance moisturizing activity on the skin. In this study, it should be mentioned that PVB5-LC could be prepared with the main compound of hydrogenated lecithin (HL) in oil-in water (O/W) emulsion. The key ingredient of humectants was contained 2% of provitamin $B_5$ ($PVB_5$) into the $PVB_5$-LC. The best suitable compositions of $PVB_5$-LC were made from 4.0 wt% of HL, 4.0 wt% of cetostearyl alcohol (CSA) as emulsifier and gelling agent, 3.0 wt% of 1,3-butylene glycol (1,3-BG) and 2.0 wt% of glycerin as moisturizers, 3.0 wt% of cyclomethicone (CMC), 3.0 wt% of isononanoate (ININ), 3.0 wt% of capric/caprylic triglyceride (CCTG), 3.0 wt% of macadamia nut oil (MNO) as emollients. As the analytical result of $PVB_5$-LC, it could know that the distribution range of particle size was 0.14 to 12.37 m level (mean size 3.24 m). It was certified the multi lamellar phase around the droplet of liquid crystal when observed the droplet particles through a polarization microscope. And it clinically was tested the effectiveness of moisturizing activity (in-vivo) compared with control sample (O/W emulsion). The effectiveness of moisturizing activity of $PVB_5$-LC with Skincon-200EX after 6 hours went up 49.0% (p<0.05, n=20) whereas the effectiveness of moisturizing activity of generally O/W emulsion cream was 25.7% (p<005, n=20). Also, in case of Comeometer CM-825, the moisturizing activity of $PVB_5$-LC after 6 hours rose 36.6% (p<0.05, n=20) whereas the effectiveness of moisturizing activity of generally O/W emulsion cream was 10.8%. Therefore, it was known that the effectiveness moisturizing activity of $PVB_5$-LC with HL was remarkably superior compared with O/W emulsion cream.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.5
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• pp.734-737
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• 2005

This study was conducted to determine the effect of effective microorganism (EM) treatment in feeding system of swine on carcass characteristics. EM pork, which reared with EM additives and EM activated liquids, and conventional pork (non-EM pork) were stored at $4^{\circ}C$. Chemical composition and storage stability of EM pork were compared with conventional pork. Cholesterol content at EM pork was 71 mg/100 g, which is lower than that of conventional pork (83 mg/100 g) when the meats were stored at $4^{\circ}C$ refrigerator. And EM pork (0.165 MDA mg/kg) showed higher antioxidant effect than control pork (0.184 MDA mg/kg). And also protein denaturalization at EM pork showed lower rate $(3.19\;mg\%)$ than that of conventional pork $(4.9\;mg\%)$ when the meats were stored at $4^{\circ}C$ refrigerator, showing that inhibitory effect of protein denaturalization was increased up to $35\%$ over the conventional pork. These results show that the EM pork had superior traits in terms of cholesterol level, lipid oxidation and protein denaturalization to the conventional pork.

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2003.10a
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• pp.105-126
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• 2003

In Korea most of annual rainfall is concentrated in several episodic heavy rains during the season of summer monsoon and typhoon. Because of uneven rainfall distribution many dams have been constructed in order to secure water supply in dry seasons. The Han River system has the most dams among Korean rivers, and the river is a series of dams now. Reservoirs need different strategy of water quality control from river water. Autochthonous organic matter and phosphorus should be the major target to be controlled in lakes. In this Paper some problems are discussed that makes efforts of water quality improvement ineffective in lakes of Korea, even after the substantial investment to wastewater treatment facilities.1) Phosphorus is the key factor controlling eutrophication of lakes and the reduction ofphosphors should be the major target of water treatment. However, water quality management strategy in Korea is still stream-oriented, and focused on BOD removal from sewage. Phosphorus removal efficiency remains as low as 10-30%, because biological treatment is adopted for both secondary treatment and advanced treatment. The standard for TP concentration of the sewage treatment plant effluent is 6 mgP/l in most of regions, and 2 mg/l in enforced region near metropolitan water intake point. TP in the effluents of sewage treatment plants are usually 1-2 mg/1, and most of plants meet the effluent regulation without a further phosphorus removal process. The generous TP standard for effluents discourages further efforts to improve phosphorus removal efficiency of sewage treatment. Considering that TP standard for the effluent is below 0.1 mg/l in some countries, it should be amended to below 0.1 mg/l in Korea, especially in the watershed of large lakes.2) Urban runoff and combined sewer overflow are not treated, even though their total loading into lakes can be comparable to municipal sewage discharges on dry days. Chemical coagulation and rapid settling might be the solution to urban runoff in regard of intermittent operation on only rainy days.3) Aggregated precipitation in Korea that is concentrated on several episodic heavyrains per year causes a large amount of nonpoint source pollution loading into lakes. It makes the treatment of nonpoint source discharge by methods of other countries of even rain pattern, such as retention pond or artificial wetland, impractical in Korea.4) The application rate of fertilizers in Korea is ten times as high as the average ofOECD countries. The total manure discharge from animal farming is thought to be over the capacity of soil treatment in Korea. Even though large portion of manure is composted for organic fertilizer, a lot of nutrients and organic matter emanates from organic compost. The reduction of application rate and discharge rate of phosphorus from agricultural fields should be encouraged by incentives and regulations.5) There is a lot of vegetable fields with high slopes in the upstream region of the HanRiver. Soil erosion is severe due to high slopes, and fertilizer is discharged in the form of adsorbed phosphorus on clay surface. The reduction of soil erosion in the upland area should be the major preventive policy for eutrophication. Uplands of high slope must be recovered to forest, and eroded gullies should be reformed into grass-buffered natural streams which are wider and resistant to bank erosion.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.36 no.2
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• pp.115-120
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• 2010

The formidable barrier property of the stratum cornemum and the high hydrophilicity of active ingredient make it difficult to permeate through the skin and reach to its site of action. The aim of this study was to investigate the effect of chemical penetration enhancers on the skin permeation of a hydrophilic cosmetic active ingredient, such as arbutin. The enhancing effects of N-methyl-2-pyrrolidone (NMP) on the permeation of a hydrophilic cosmetic active ingredient were evaluated by using Franz diffusion cell. The study indicated that NMP has considerable influence on the skin permeability. NMP was not only the most effective enhancer but also increased the skin permeability of arbutin approximately 1.3~1.5 fold compared with control without penetration enhancer. The lag time did not change with NMP, which suggested no effect of NMP on skin lipid fluidity. This suggest that arbutin co-permeated with NMP. The results indicate NMP is effective enhancer of a hydrophilic cosmetic active ingredient in penetration, with potential applications for drug delivery system.

• Korean Journal of Acupuncture
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• v.17 no.1
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• pp.101-121
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• 2000

The purpose of this morphological studies was to investigate the relation to the meridian, acupoint and nerve. The common locations of the spinal cord and brain projecting to the the gallbladder, GB34 and common peroneal nerve were observed following injection of transsynaptic neurotropic virus, pseudorabies virus(PRV), into the gallbladder, GB34 and common peroneal nerve of the rabbit. After survival times of 96 hours following injection of PRV, the thirty rabbits were perfused, and their spinal cord and brain were frozen sectioned($30{\mu}m$). These sections were stained by PRV immunohistochemical staining method, and observed with light microscope. The results were as follows: 1. In spinal cord, PRV labeled neurons projecting to the gallbladder, GB34 and common peroneal nerve were founded in thoracic, lumbar and sacral spinal segments. Densely labeled areas of each spinal cord segment were founded in lamina V, VII, X, intermediolateral nucleus and dorsal nucleus. 2. In medulla oblongata, The PRV labeled neurons projecting to the gallbladder, GB34 and common peroneal nerve were founded in the A1 noradrenalin cells/C1 adrenalin cells/caudoventrolateral reticular nucleus, rostroventrolateral reticular nucleus, medullary reticular nucleus, dorsal motor nucleus of vagus nerve, nucleus tractus solitarius, raphe obscurus nucleus, raphe pallidus nucleus, raphe magnus nucleus, gigantocellular nucleus, lateral paragigantocellular nucleus, principal sensory trigeminal nucleus and spinal trigeminal nucleus. 3. In Pons, PRV labeled neurons were parabrachial nucleus, Kolliker-Fuse nucleus and cochlear nucleus. 4. In midbrain, PRV labeled neurons were founded in central gray matter and substantia nigra. 5. In diencephalon, PRV labeled neurons were founded in lateral hypothalamic nucleus, suprachiasmatic nucleus and paraventricular hypothalamic nucleus. 6. In cerebral cortex, PRV labeled neuron were founded in hind limb area.This results suggest that PRV labeled common areas of the spinal cord projecting to the gallbladder, GB34 and common peroneal nerve may be first-order neurons related to the somatic sensory, viscero-somatic sensory and symapathetic preganglionic neurons, and PRV labeled common area of the brain may be first, second and third-order neurons response to the movement of smooth muscle in gallbladder and blood vessels.These PRV labeled neurons may be central autonomic center related to the integration and modulation of reflex control linked to the sensory system monitoring the internal environment, including both visceral sensation and various chemical and physical qualities of the bloodstream. The present morphological results provide that gallbladder meridian and acupoint may be related to the central autonomic pathways.