• Journal of Korean Neurosurgical Society
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• v.29 no.12
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• pp.1642-1649
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• 2000

Objectives : Transverse myelitis(TM) is characterized by bilateral motor, sensory, and autonomic dysfunction of the spinal cord in the absence of pre-existing neurologic disease. It is an uncommon but not rare condition. But it remains as poorly understood syndrome not only etiologically but also in terms of its clinical behavior. Neurosurgically, It is often quite difficult to distinguish from other surgical intramedullary lesions. We present our clinical experiences of TM in order to assess its clinical behavior and to define the radiological characteristics that can distinguish TM from other intramedullary lesions. Methods : From June 1991 to May 1997, twenty-nine patients with transverse myelitis were admitted to our department. All cases revealed acute or subacute syndrome of non-compressive myelopathy and intramedullary lesions in the MRI. We analyze the radiological data and medical records retrospectively. Results : Patients ranged in age from 16 to 66 years, with 22 males and 7 females. Mean follow-up period was 53 months. For the offending levels, cervical was 5, thoracic 21, and lumbar 3 in number. The patients who presented the return of symptoms after a diminution or abatement of initial symptoms were 7(24%). In the MRI, TM showed typical characteristics of high signal intensity lesions in the center of spinal cord in T2 weighted images and low- to iso-signal intensity in T1 weighted images. A focal nodular enhancement pattern was observed in 58.6%(17/29) of the patients. MR follow-up studies were done in the 21 patients and radiological improvement were verified. Biopsies were done in 3 patients. Normal to good outcome was achieved in 62% of the patients. Conclusion : Transverse myelitis has characteristic radiological findings that can be distinguished from other intramedullary lesions. In our series, it is associated with significant recurrence rates thus, should not be considered a selflimiting disease with good prognosis.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.1
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• pp.54-62
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• 2018

Objective: Due to the threat of global warming, the livestock industry is increasingly interested in exploring how feed additives may reduce anthropogenic greenhouse gas emissions, especially from ruminants. This study investigated the effect of Rhodophyta supplemented bovine diets on in vitro rumen fermentation and rumen microbial diversity. Methods: Cannulated Holstein cows were used as rumen fluid donors. Rumen fluid:buffer (1:2; 15 mL) solution was incubated for up to 72 h in six treatments: a control (timothy hay only), along with substrates containing 5% extracts from five Rhodophyta species (Grateloupia lanceolata [Okamura] Kawaguchi, Hypnea japonica Tanaka, Pterocladia capillacea [Gmelin] Bornet, Chondria crassicaulis Harvey, or Gelidium amansii [Lam.] Lamouroux). Results: Compared with control, Rhodophyta extracts increased cumulative gas production after 24 and 72 h (p = 0.0297 and p = 0.0047). The extracts reduced methane emission at 12 and 24 h (p<0.05). In particular, real-time polymerase chain reaction analysis indicated that at 24 h, ciliate-associated methanogens, Ruminococcus albus and Ruminococcus flavefaciens decreased at 24 h (p = 0.0002, p<0.0001, and p<0.0001), while Fibrobacter succinogenes (F. succinogenes) increased (p = 0.0004). Additionally, Rhodophyta extracts improved acetate concentration at 12 and 24 h (p = 0.0766 and p = 0.0132), as well as acetate/propionate (A/P) ratio at 6 and 12 h (p = 0.0106 and p = 0.0278). Conclusion: Rhodophyta extracts are a viable additive that can improve ruminant growth performance (higher total gas production, lower A/P ratio) and methane abatement (less ciliateassociated methanogens, Ruminococcus albus and Ruminococcus flavefaciens and more F. succinogenes.

• KDI Journal of Economic Policy
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• v.24 no.1
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• pp.113-190
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• 2002

The purpose of this paper is to perform empirical studies on the impact of pollution intensity on international competitiveness using 1993 and 1998 data, and to estimate the change in environmental regulation level faced by the firms during 1993~1998. Collecting relevant data and providing them for further studies in the area are another purposes of the paper. The first method is the regression of various indices of international competitiveness on factor costs, such as labor, capital, R&D and pollution abatement costs. Goal of the regression analysis is to estimate the scarcity and comparative advantage effect of each production factor, especially environmental resource. Regression results show that those industries which employ more environmental resource have higher comparative advantage in both years, which implies that Korean firms are endowed with abundant environmental resource compared to other countries. The second method is to compute the relative scarcity indices(HOVL indices) of production factors, proposed by Leamer based on Vanek's generalized Hecksher-Ohlin Theorem. This method estimates the relative scarcity of production factors by computing factor costs embodied in import and export of commodities. This method shows similar results as the regression method; i.e., trade pattern of production factors implies that the manufacturing sector in Korea is endowed with abundant environmental resource compared to other countries. Considering population density, water resource endowment, intensity of economic activity per unit area and current air and water pollution levels, it is evident that Korea is never endowed with abundant environmental resource compared to other countries. Then the abundance of environmental resource revealed by the trade patterns of commodities and production factors implies that Korea's environmental regulation level is excessively generous compared to environmental capacity, and that this increased the environmental resource endowment supplied to firms and thus distorted the inter-industry comparative advantages. Both regression and HOVL methods, on the other hand, show that overall environmental regulation level faced by the firms has been strengthened during 1993~1998.

• Journal of Korean Society of Rural Planning
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• v.25 no.4
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• pp.47-56
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• 2019

More than half of the nonpoint sources of polluting water occur in cultivating farmlands in rural areas. Agricultural nonpoint sources are discharged from large areas of farmlands, making it difficult to collect or treat pollutants. Farmland source management is known to be the most effective, and preventive management by improving farming methods is the key to reduce nonpoint pollution. At present, more than 30% of the pollutants flowing into the rivers and lakes are nonpoint pollutants caused by agricultural activities. As a countermeasure, it is more preferable to develop and apply optimal farming management techniques for agricultural nonpoint pollution management basically than to apply existing water quality management techniques. Because of the characteristics of nonpoint source pollution, it is necessary to manage farmlands in rural areas, so the willingness and competence of the residents is most important. The purpose of this study is to analyze and understand the process of changing the cognition of residents through capacity education and survey for nonpoint pollution management in rural areas. This study conducted intensive resident competency education and examined the process of changing resident awareness through three surveys. As a result of this study, it was found that continuous education and activities for rural non-point pollution management are necessary for raising awareness of residents and managing non-point pollution effectively, showing possibility of change residents' perception.

• Applied Chemistry for Engineering
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• v.20 no.4
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• pp.407-410
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• 2009

18~19 wt% $KMnO_4$/$SiO_2-Al_2O_3$ with Si/Al = 1/5 and 1/10, and 20 wt% $KMnO_4$/$Al_2O_3$ were prepared by solvent evaporation method. Catalytic activity of ethylene abatement over those samples were evaluated and compared under the conditions of GHSV $1125h^{-1}$, ethylene gas (ethylene 0.2%, air 99.8%, relative humidity 50%) at 30, 40, 60 and $120^{\circ}C$ using a fixed-bed reactor. $KMnO_4$/$SiO_2-Al_2O_3$ was showed better performance than $KMnO_4$/$Al_2O_3$ by 170~210% at 30, $40^{\circ}C$, and by 60% at 60, $150^{\circ}C$, respectively.

• Microbiology and Biotechnology Letters
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• v.50 no.2
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• pp.165-192
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• 2022

The microbial metagenome characteristics of bioaerosols and particulate matter (PM) in the outdoor atmospheric environment and the effects of climate and environmental factors on the metagenome were analyzed. The concentrations of bacteria and fungi in bioaerosols and PM were determined by sampling different regions with different environmental properties. A variety of culture-independent methods were used to analyze the microbial metagenome in aerosols and PM samples. In addition, the effects of meteorological and environmental factors on the diversity and metagenomes of bacteria and fungi were investigated. The survival, growth, and dispersal of the microorganisms in the atmosphere were markedly affected by local weather conditions and the air pollutant concentration. The concentration of airborne microorganisms increased as the temperature increased, but their concentration decreased in summer, due to the effects of high temperatures and strong ultraviolet rays. Humidity and microbial concentration were positively correlated, but when the humidity was too high, the dispersion of airborne microorganisms was inhibited. These comprehensive data on the microbial metagenome in bioaerosols and PM may be used to understand the roles and functions of microorganisms in the atmosphere, and to develop strategies and abatement techniques to address the environmental and public health problems caused by these microorganisms.

• Journal of Environmental Impact Assessment
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• v.28 no.2
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• pp.101-112
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• 2019

Over the last few years, air pollution ($PM_{10}$, $PM_{2.5}$) in the Seoul metropolitan area (SMA) has emerged as one of the most concerned and threatening environmental issues among the residents. It brings about various harmful effects on human health, as well as ecosystem and industrial activities. Governments and individuals pay various costs to mitigate the level of air pollutants. This study aims to empirically find the willingness to pays (WTP) among the parents from different socio-cultural groups - international and domestic groups to mitigate air pollution ($PM_{10}$, $PM_{2.5}$) in their residential area. Contingent Valuation Methods (CVM) is used with employing single-bounded dichotomous choice technique to elicit the respondent's WTP. Using tobit (censored regression) and probit models, the monthly mean WTP of the pooled sample for green electricity which contributes to improve air quality in the region was estimated as 3,993 KRW (3.58 USD). However, the mean WTP between the international group and domestic group through a sub-sample analysis shows broad distinction as 3,325KRW (2.98 USD) and 4,449 KRW (3.98 USD) respectively. This is because that socio-cultural characteristics of each group such as socio-economic status, personal experience, trust in institutions and worldview are differently associated with the WTP. Based on the results, the society needs to raise awareness of lay people to find a strong linkage between the current PM issue and green electricity. Also, it needs to improve trust in the government's pollution abatement policy to mobilize more assertive participation of the people from different socio-cultural background.