• Molecular & Cellular Toxicology
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• v.5 no.3
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• pp.265-271
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• 2009

Concentrations of industrial, agricultural and natural chemicals have been increasing in secondary effluents without their combined sub-lethal effects having been elucidated. In this study, two assays (the comet and acetylcholinesterase assays) were combined to evaluate the genotoxic and neurotoxic effects of effluent from the Noksan wastewater treatment plant (WWTP) on two local marine fish species (flounder and sea eel). The fish were exposed to WWTP secondary effluent that had been diluted with filtered seawater to final concentrations of 1%, 10% and 50%. Analysis of fish samples collected 3 and 5 days after exposure showed that DNA damage occurred in flounder exposed to 50% effluent and in sea eels exposed to 10% or 50% effluent. Furthermore, it was found that acetylcholinesterase (EC:3.1.1.7, AChE) activity decreased in both species when exposed to 10% effluent, indicating the presence of large amounts of genotoxic and neurotoxic chemicals in the effluent. Our results indicate that the comet and AChE assays are promising tools for biomonitoring of secondary effluents.

• KIEAE Journal
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• v.7 no.4
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• pp.127-133
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• 2007

As a fundamental study on the corrosion resistance of reinforced concrete structures using Natural Inorganic Minerals exposed to carbonation environment, The test specimens were concrete(W/C=60%) with Natural Inorganic Minerals content of 0%, 10%. Accelerated carbonation and autoclave corrosion accelerated curing were then conducted with them. The corrosion resistance of steel in concrete with Natural Inorganic Minerals content of 0%, 10% was examined by corrosion form, half-cell potential, polarization resistance, corrosion area and weight loss after 24 hours of autoclave corrosion accelerated curing.The results of the study showed that as for steel in concrete with Natural Inorganic Minerals content of 10%, the corrosion resistance was more excellent than steel in concrete with Natural Inorganic Minerals content of 0%.

• Journal of Korean Society on Water Environment
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• v.38 no.2
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• pp.72-81
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• 2022

Numerous studies have investigated the occurrence and fate of microplastics in the environment; however, only limited effort has been devoted to exploring the characteristics of dissolved organic matter (DOM) leached from microplastics. In microplastic (MP)-contaminated environment, MPs are typically mixed with naturally-occurring particles, which interferes with their detection in the environment. Thus, it is necessary to distinguish between the DOM leached from MPs and those leached from natural particles and also to characterize their properties. This study investigated DOM leaching behavior from MPs (polystyrene: PS, polyvinylchloride: PVC) and natural particulates (forest soil: FS, litter leaves: LL) under light, which is considered one of the main weathering processes that affect MPs in the environment. The leached DOM concentrations and fluorescence characteristics were compared under dark versus light conditions. Regardless of the origins, UV light promoted DOM release from all the particulates. More DOM was released from natural particles than from MPs under both conditions. However, the effect of promoting DOM release by UV was more pronounced for MPs than for natural particles. It was observed from fluorescence spectra that the intensity of the humic-like region was substantially reduced when MP-derived DOM was exposed to UV light, whereas the change of intensity was very little for natural particles. Under light conditions, the ratio of protein-like to humic-like fluorescence of MP-derived DOM was higher than that of DOM from natural particles. This study implies that a substantial amount of DOM could be leached from MPs even in MP-polluted environment under UV irradiation. Protein/humic fluorescence ratio could be utilized as a fast probing indicator to separate the two sources of particles under light.

• The Journal of Sustainable Design and Educational Environment Research
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• v.11 no.1
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• pp.23-31
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• 2012

The number of school crime has grown continuously for last ten years and its intensity also has reached to serious condition. The concept of CPTED(Crime Prevention through Environmental Design) needs to be focused for improving school environment regarding this context. The exterior space of school environment is variously exposed to school crimes committed by colleague students and also intruders. From the perspective of school CPTED, Natural surveillance as one of the practical strategies requires the micro-scale analysis which clarifies local visibility at each different school exterior space. Thus, the purpose of this research is to develop the analysis method clarifying visibility condition at exterior space of school environment, which supports finding the condition of natural surveillance. The programmed analysis algorithm generated quantitative results clarifying Degree for static visibility and Clustering Coefficient for user tracking visibility. The result of this study produced the analysis method feasible to clarify weak natural surveillance conditions at school exterior spaces. Also, it is expected that the developed analysis method will be used to improve the layout of school exterior space from the perspective of CPTED.

• Journal of the Korean Society of Clothing and Textiles
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• v.14 no.3 s.35
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• pp.229-240
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• 1990

The purpose of this study was to investigate the effect of hydrophilicity of the fiber on the water vapor transport properties of the fabric by using double layered fabrics of natural and synthetic fibers such as cotton, wool, nylon, dacron, orlon and polypropylene. Wickability and absorption rate were measured to determine the absorbancy of the fabrics. Dynamic and steady state water vapor transport properties were measured by cobaltous chloride method and evaporation method, respectively. Absorption was in the order of orlon> cotton > wool > nylon > polypropylene > dacron. Dynamic surface wetness of synthetic fabrics were faster than that of natural fabrics. For the double layered fabrics, higher water vapor transport was resulted when the natural fabric was exposed to lower vapor pressure and synthetic fabric was exposed to higher vapor pressure than when the fabrics were layered the other way around. Opposite result was obtained for orlon, which suggested that when the fabric of high absorbancy is exposed to the environment and lower absorbancy is to the skin, higher water vapor transpont could be resulted.

• Journal of Environmental Science International
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• v.12 no.2
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• pp.151-155
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• 2003

The resources conservation system is comprehended, making Taean-haean National Park a research material by applying the fact of landowning, designating an LOP and Korea and Japan's Natural Park Act. Following conclusions were obtained in this study; Most of land areas of the National Park are privately owned; Only a few have been designated as Natural Reservation, a core reserved area on LOP, and a sandy beach, a sand dune, a sand spit, a tidal flat, a wetland, etc are distributed in the natural environment area so they were exposed to development; As seen in most of coastal type of National Parks, 13 commercial beaches are established. The annual rush to the beaches appears in July and August; Sand dune areas that have to be managed in terms of conservation, are turned into beaches. Moreover, the collective facilities areas are randomly developed. So they fail to function originally; The current Natural Park Act has no systematic devices for conservation of the natural resources on the seashore or offshore.

• Journal of People, Plants, and Environment
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• v.22 no.2
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• pp.127-143
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• 2019

This study investigates the color stimuli of two varieties of foliage plants by extracting electroencephalogram, electrocardiogram and physiology activity data from 30 participants in their 50s or older. Changes in the physiological activity of subjects against six color stimuli were examined. The stimulus to real green plants 'Silver Queen' was set as the control group, and was compared with other groups including the stimulus to real 'Angel' plants and four stimuli to artificial colors (two color images and color schemes of the same green and red plants). Compared to the five groups, the relative theta power spectrum (RT) and the ratio of alpha to high beta (RAHB) increased in the subjects exposed to real green plants. This result demonstrates that the green plant ('Silver Queen') increases the stability, relaxation, and internal concentration of subjects in a proper state of awakening. The result of this experiment showed a statistically significant difference in the level of RT when subjects were exposed to the groups of real green and red plants. This finding indicates that the green plant increases internal concentration more than the red plant. RT and the relative low beta power spectrum (RLB) in the groups of natural colors were higher than the groups of artificial colors when subjects focused their mind on the two types of real plants. However, the level of relative mid beta power spectrum (RMB), ratio of SMR to theta (RST), ratio of mid beta to theta (RMT), relative high beta power spectrum (RHB), and spectral edge frequency 95% were higher when subjects were exposed to the photos and colors scheme of plants than when they were exposed to real plants. The subjects experienced more "comfortable" emotions when they were looking at plants with green colors. Overall, it is recommended to use the natural colors of real plants in places where which stability and relaxation are required. On the contrary, the artificial colors of plants such as their photos and color schemes are useful in places where a high level of concentration is required in a short period of time.

• Molecular & Cellular Toxicology
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• v.2 no.3
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• pp.170-175
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• 2006

The extensive isolation of genes responsive to stressful conditions from a soft coral Scleronephthya gracillimum was described. Soft coral colonies were exposed to thermal and chemical stressors to induce the expression of stress related genes. Differentially expressed genes by natural or anthropogenic stressors were identified by construction of standard and stress exposed-paired subtractive cDNA library. Thirty-two and thirty-seven kinds of candidate genes were identified from thermal or benzo[a]pyrene stress exposed group, respectively, which are associated with cell cycle, cell signaling, transcription, translation, protein metabolism, and other cellular functions. The expected function of each gene was described. The isolated and identified differentially expressed genes have a great potential to identify environmental stressors in global environmental changes and could act as molecular biomarkers for biological responses against environmental changes. Finally, it may open a new paradigm on soft coral health assessment.

• Journal of Environmental Science International
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• v.2 no.2
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• pp.29-29
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• 1993

Shingal reservoir is a relatively small (211ha) and shallow impoundment, and approximately 25 ha of its sediment is exposed after spring drawdown. At least 14 vascular p13n1 species germinate on the exposed sediment, but Persimria vulgaris Webb et Moq. quickly dominates the vegetation. In order to estimate the role of the vegetation in the dynamics of heavy metal pollutants in the reservoir, Cu concentration of water, fallout particles, exposed sediment, and tissues of p. vulgaris, Ivas analyzed. Cu content in reservoir water decreased from $13.10mg/m^2$ on May 15 (before dralvdown) to $3.08mg/m^2$ in June 1 (after drawdown), mainly due to the loiwering of water level. Average atmospheric deposition of Cu by fallout particles was $10.84 {\mu}g/m^2/day$. Cu content in the surface 15cm of exposed sediment decreased from $5.094g1m^2$ right after drawdown, to $0.530g/m^2$ in 41 days, which is a 89.6% decrease. Therefore up to 99.7% of Cu in the reservoir appears to exist in the sediment. only 0.3% in water If the rate of atmospheric Input by fallout particles is assumed to have been the same since 1958, when the reservoir was completed, cumulative input of Cu during the 38 years would have been $150.35mg/m^2$, which is only 3.0% of Cu content in sediment right after drawdown. Therefore, most of Cu in the Shingal reservoir must have been transported by the Shingal-chun flowing into the reservoir, Standing crop of vegetation on the exposed sediment 41 days after drawdown was $730.67g/m^2$, of which 630.91g/m2 was p. vulgaris alone, and Cu content in P vulgaris at this time was $6.612mg/m^2$. This was only 0.13% of Cu in the exposed sediment, but was 50.5% of Cu in water before drawdown, or 167% of the average annual input of Cu by atmospheric deposition. If other plants were assumed to absorb Cu to the same concentration as p. vulgaris, total amount of Cu absorbed in 41 days by vegetation on the exposed sediment is estimated to be 1913.3 g, which is a considerable contribution to the purification of the reservoir water.

• The Journal of Natural Sciences
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• v.19 no.1
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• pp.27-35
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• 2008

The importance of microbial activity in the alteration and deterioration of stone and concrete walls has been frequently neglected. Organisms present on stone monuments can include photolithoautotrophs, such as algae, cyanobacteria, mosses, and higher plants. Because of their ability to survive repeated drying and rehydration cycles and high UV levels, the cyanobacteria are particularly important on exposed surfaces. The cyanobactria distributed on the surface of the stone cultural heritages in Gwanschoksa, Nonsan city were investigated. Chlorococcus sp. Aanabaena sp. Gloeocapsa sp Lyngbya sp. Stigomena sp. Synechocystis sp were identified. Haplaosiphon fontinalis and Stigonema turfaceum, which were not recoded is Korea, were also identified. Cells often have thick pigmented sheath in dry, sun-exposed environment and shorter filament, which can be different than that in aquatic systems. Special attention should be paid to production of an adequate DNA database in order to accelerate the rate at which information on the species present in biofilms become available.