• Korean Journal of Environmental Agriculture
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• v.30 no.1
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• pp.68-75
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• 2011

BACKGROUND: To assess and prevent the environmental impacts and risks by veterinary pharmaceuticals, Guidance on Estimating Soil Persistence and Degradation Kinetics from Environmental Fate Studies on Veterinary Pharmaceuticals for Environmental Risk Assessment was proposed. METHODS AND RESULTS: Proposed guidance was coined by VICH, EU guideline, OECD guideline and soil dissipation studies for the purpose of international harmonizing. Guidance was also modified from pesticide soil persistence testing guidelines of US, EU, and Korea, with practical approaches adopting in-use test guideline for Korea. CONCLUSION(S): Proposed guidance are consisted of three parts; Laboratory Soil Experiment, Field Soil Dissipation Study, and Estimation of $DT_{50}/DT_{90}$. Proposed guidance is to be available for the requirement for registration of veterinary pharmaceuticals with fit for purpose in Korea.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.12 no.1
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• pp.24-31
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• 2007

Global fates of polychlorinated biphenyl(PCB) were investigated with a fugacity based multimedia transport and fate model, Globe-POP(persistent organic pollutant). The accumulation of PCB was directly affected by the emission patterns of PCB into the atmosphere and surface areas of environmental compartments. Partition coefficients and reaction rates also influenced on the accumulation patterns of PCB. The emission patterns of PCB in 10 climate zones were consistent for the past 70 years, while the contribution of PCB in high-latitude zones to the globe has increased by cold condensation. Considering the amounts of emission and accumulation of PCB, the North temperature zone is regarded as an important source and sink of PCB. Meanwhile, in spite of no significant sources, POPs accumulate in Antarctic environments mainly due to extremely low temperature. Finally we suggested that a global water balance accounting for snow/ice should be incorporated into multimedia environmental models for high-latitude zones and polar regions with the seasonal snow pack and/or permanent ice caps. The modified model will be useful to evaluate the influence of climate change on the fate of POPs.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2001.05b
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• pp.109-112
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• 2001

A case study of foodwaste treatment was conducted to compare the impacts of four scenarios: incineration, incineration after biogasification, biogasification followed by composting, and composting. Potential contributions to climate change, acidification, consumption of landfill and human toxicity were assessed. Characterization of human toxicity caused by metals and PCDD/DF was performed by three multimedia fate models. Scenarios with a biogasification process showed lower impact on climate change and human toxicity. The ranking of four scenarios on human toxicity varied depending on the characterization models applied. The steady state models placed high priority on emission of heavy metals to farmland, whereas the dynamic model estimated the emission of PCDD/DF from the incineration process as more significant.

• Journal of Ship and Ocean Technology
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• v.1 no.2
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• pp.41-49
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• 1997

We reviewed various oil-spill models and condensed the integrated information into a prediction model, “Green Sea Ranger”which is applicable to Korean coastal area. The developed software consists of pre- and post-modules for environment setup and display of results and main module for the prediction of oil\`s fate. In the pre-module target areas can be selected from the included geographic information system and various environmental and optional numerical data for the prediction can be input through easy GUI or imported from the database we established. For the fate of the spilt oil we included effects of spreading, advection, evaporation, and emulsification. Preliminary numerical experiment has proved that the developed oil-spill prediction system can be easily utilized in on-site oil recovery operations which usually require a quick and reasonable prediction.

• Journal of Korean Society on Water Environment
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• v.22 no.3
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• pp.527-533
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• 2006

Tetracycline is one of the mostly used antibiotics around the world. The purpose of this study was to evaluate the fate of two different types of tetracycline resistant bacteria in biological wastewater treatment plants. Tetracycline resistant enterics and heterotrophic bacteria were monitored under two different lab-scale experimental conditions. Tetracycline resistant enteric bacteria showed the lower percentages of total enteric bacteria and net specific growth rate in the monitored activated sludge system as compared to tetracycline resistant heterotrophic bacteria. Therefore, total enterics, potentially E.coli, might not be the best indicator microorganism for evaluating the antibiotic resistant bacteria in biological wastewater treatment plant.

• International Journal of Stem Cells
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• v.15 no.1
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• pp.14-25
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• 2022

Glia have been known for its pivotal roles in physiological and pathological conditions in the nervous system. To study glial biology, multiple approaches have been applied to utilize glial cells for research, including stem cell-based technologies. Human glial cells differentiated from pluripotent stem cells are now available, allowing us to study the structural and functional roles of glia in the nervous system, although the efficiency is still low. Direct conversion is an advanced strategy governing fate conversion of diverse cell types directly into the desired lineage. This novel strategy stands as a promising approach for preliminary research and regenerative medicine. Direct conversion employs genetic and environmental cues to change cell fate to that with the required functional cell properties while retaining maturity-related molecular features. As an alternative method, it is now possible to obtain a variety of mature cell populations that could not be obtained using conventional differentiation methods. This review summarizes current achievements in obtaining glia, particularly oligodendrocytes and Schwann cells.

• Journal of Korean Society on Water Environment
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• v.37 no.5
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• pp.355-362
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• 2021

This study investigated the fate of dissolved organic matter (DOM) in a water reclamation facility (WRF) in Korea. The WRF consists of coagulation, sedimentation, microfiltration, and reverse osmosis (RO) components. The production capacity of WRF is 90,000 m³/day. The reclaimed water is reused as industrial water. We also characterized DOM in raw, processed, and finished waters based on analysis of dissolved organic carbon (DOC), ultraviolet absorbance at 254 nm (UVA₂₅₄), fluorescence excitation emission matrix (FEEM), and DOC fractions via liquid chromatography-organic carbon detection (LC-OCD). Based on the results of DOC, UVA₂₅₄, and FEEM analyses, neither the coagulation/sedimentation nor the microfiltration at the WRF effectively removed DOM. The RO process removed more than 94% of DOM. The raw water (i.e., secondary treated effluent obtained from a wastewater treatment plant) exhibited tryptophan-like peaks, which are a promising marker of wastewater, in the FEEM analysis. Coagulation and microfiltration failed to eliminate the wastewater marker, whereas RO completely removed it. The raw water also carried high levels (89.4%) of hydrophilic and low-molecular weight substances, which are difficult to remove via coagulation-sedimentation or microfiltration. Humic substance was a major component of the hydrophilic fractions. Based on the LC-OCD analysis, RO effectively removed the humic and polymeric materials from DOM.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2003.10a
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• pp.31-32
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• 2003

A dynamic multimedia model with 2-dimensional spatial resolution, POPsME (Persistent Organic Pollutants in Multimedia Environments), was evaluated by comparing predicted relative concentrations with those measured. A total of 12 polycyclic aromatic hydrocarbons (PAHs) were tested (phenanthrene, anthracene, fluoranthene, pyrene, chrysene, benz (a)anthracene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, dibenz(a,h)anthracene, benzo(g,h,i)perylene, and indeno(1,2,3-c,d)pyrene). The concentrations were measured in air particulates, water (dissolved phase and suspended solids (ss)), soil, sediment, and leaves of Pinus koraiensis and Prunus serrulata at seven sites in the Seoul and neighboring area (150km x 150km), Korea.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.955-960
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• 2012

In most agricultural soils, ammonium ($NH_4{^+}$) from fertilizer is quickly converted to nitrate ($NO_3{^-}$) by the process of nitrification which is crucial to the efficiency of N fertilizers and their impact on the environment. The salinity significantly affects efficiency of N fertilizer in reclaimed tidal soil, and the soil pH may influence the conversion rate of ammonium to nitrate and ultimately affect nitrogen losses from the soil profile. Several results suggest that pH has important effects on recovery of fall-applied N in the spring if field conditions are favorable for leaching and denitrification except that effects of soil pH are not serious under unfavorable conditions for N loss by these mechanisms. Soil pH, therefore, deserves attention as an important factor in the newly reclaimed tidal soils with applying N. However, fate of N studies in a newly reclaimed tidal soils have been rarely studied, especially under the conditions of saline-sodic and high pH. Therefore, understanding the fate of nitrogen species transformed from urea treated into the reclaimed tidal soil is important for nutrient management and environmental quality. In this article, we reviewed yields of rice and fate of nitrogen with respect to the properties of reclaimed tidal soils.

• Advances in environmental research
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• v.2 no.3
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• pp.179-202
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• 2013

Bisphenol A and other alkylphenols are widely used in plastic and other industrial consumer products. Release of these compounds into the aquatic environment during their manufacture, use and disposal has been a great scientific and public concern due to their toxicity at high concentrations and endocrine disrupting effects at low concentration on aquatic wildlife and human beings. This paper reviews the published data and researches on the environmental occurrence, distribution, health effects and analytical techniques of bisphenol A and alkylphenols. The aim is to provide an overview of the current understanding about bisphenol A and alkylphenols in the environment and the difficulties faced today in order to establish standard and systematic environmental analysis and assessment process for these endocrine disruptor compounds.