• Explosives and Blasting
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• v.28 no.2
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• pp.86-98
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• 2010

As the quality of life is being upgraded, the public complaints about noise and vibration from construction sites are growing. Despite the disputes over the blasting damage on aquatic lives in river, ocean, and aquarium near construction sites tend to increase, most of existing solutions or regulations on the damages caused by blasting are established for the damages on land. Although the estimated amount of damage is up to several millions of USD, there is no guideline for resolving the dispute related to the underwater vibration. This paper presents an example where the public grievance about the underwater noise was successfully resolved by elucidating the characteristics of underwater sound, deducing the correlations between ground vibration and underwater sound during blast, and predicting the underwater sound level during blasting from the ground vibration measured on the ground near an aquarium basin.

• Journal of Environmental Impact Assessment
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• v.26 no.5
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• pp.344-353
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• 2017

Cambodia is a typical country that a very famous tourist destination in South Asian regions, but water has some serious problems. As a public hygiene point of view, water problems in Cambodia can be roughly classified into two categories. A numbers of the report revealed that thermotolerant coliform(TTC) bacteria and arsenic(As) pollution representative species as a representative pollutant for surface water and ground water problems, respectively. In recent years, home water purifier systems for various filter systems including BSF(Bio-Sand Filter), MF and RO have been spread and adopted in rural areas. However, BSF and composite membrane processes are recognized as an undesirable and representative method due to unreliable efficiency, high cost and maintenance issues. In order to develop a small-scale ceramic filter as a home water purifier, the applicability of two types of gravity ceramic filter using clay and red soil in the part of the Northwest was made and compared in this research.

• Development and Reproduction
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• v.4 no.1
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• pp.109-114
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• 2000

The present study was undertaken to examine the effects of ethanol on the ovarian steroidogenic acute regulatory protein(StAR) gene expression during prepubertal and onset of puberty. From day 25, each rat began receiving either a control saline or ethanol. Animals were sacrificed on day 27 and 32, and their ovaries and blood were collected. In the present results, ethanol treatment significantly decreased serum luteinizing hormone contents at both time points. Uterine weights of ethanol-treated group were significantly lighter than control group at early time point while there was no noticeable discrepancy at late time point. Vaginal openings, a marker of onset of puberty, also clearly delayed in ethanol-treated group. Using an in situ hybridization histochemistry, we determined the expression of mRNAs encoding StAR. Ovaries from ethanol-treated rats showed a suppresed expression of StAR mRNA. These results demonstrate that ethanol can disturb the prepubertal ovarian function and onset of puberty, at least in part, through the inhibition of ovarian StAR gene expression.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.23 no.2
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• pp.108-113
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• 2013

Objectives: Although several cases of lung diseases caused by indium have been reported in Japan, the United States and China, South Korea, which is estimated to have been the world's largest consumer of indium, has not yet established a criteria for the diagnosis of lung diseases caused by indium exposure. In this study, we tried to determine the applicability of the Krebs von den lungen-6, which has been widely recognized for its use with interstitial lung disease in Japan, as a biological exposure index for indium. Methods: Methods: The analysis of indium in serum was conducted by inductively coupled plasma mass spectrometry and the analysis of KL-6 in serum was carried out using enzyme-linked immunosorbent assay kit. Results: The indium levels in serum were distributed from below the detection limit to a peak of $125.78{\mu}g/L$, and the values of the KL-6 were distributed from 104.5 U/mL to 2162.2 U/mL. The serum indium and KL-6 showed good correlation ($R^2$=0.389,pfortrend=0.000) and smoking did not affect the KL-6. Conclusions: The usefulness of KL-6 as a specific biomarker for interstitial lung disease has been recognized. In addition, it is expected that effective prevention of health problems can be achieved by determining the lung-damage progress at an early stage according to individual susceptibility.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.2
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• pp.194-199
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• 2010

Compost as a soil amendment is of importance in enhancing the soil chemical and microbial qualities; however, soil microbial community can vary depending on the composition, and the amount of compost applied to plant in the soil. Responses of soil microbial properties to compost applications with 0, 30, and 60 Mg $ha^{-1}$ were investigated in silt loam soils where red pepper(Capsicum annuum L.) was mainly cultivated in Yeongyang, Gyeongbuk, Korea. The analysis of phospholipid fatty acids (PLFAs) extracted from soil showed that compost amounts significantly increased PLFAs representing as bacteria, fungi, and VAM-fungi as well as the ratio of fungi/bacteria, and monounsaturated/saturated PLFAs. Increasing the amount of compost significantly increased Gram-/Gram+ PLFAs' ratio, but significantly decreased monounsaturated/saturated PLFAs' ratio. Therefore, this result shows that compost would vary to a limited extent the microbial community in red pepper field. However, increase in compost application would change the subgroup structure of microbial community only.

• Development and Reproduction
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• v.9 no.2
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• pp.85-93
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• 2005

Estrogens are known as the steroid hormones and essential regulators of developments, differentiations, and fertility in animals including humans. Recently, classic focus on estrogens which are considered as female hormone is changing in the whole field of reproductive endocrinology. Especially, interest in estrogen functions in male reproduction is increasing more and more, as numerous studies about the endocrine disruptors, interrupting the endocrine system, are being carried out. To understand exactly the function of estrogen in a male reproductive system, a summary for estrogen receptors upon developmental distributions in testis will be useful. In addition to the regulatory roles of estrogen in male, unexpected exposure to exogenous estrogens causes defects of differentiation of male reproductive system and an injury of spermatogenesis. Also, this review highlights the indicator of exogenous estrogens to perturb male fertility. These approaches would give tile practical information about estrogen roles in male development and reproduction.

• Development and Reproduction
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• v.14 no.2
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• pp.75-82
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• 2010

The objective of this study is to identify the effects of endurance exercise and selenium on mitochondrial transcription factor in old Goto-Kakizaki (GK) rats. In this experiments, endurance exercise were treadmill-run at 24 m/min, 30 min/day, 5 days/week, 6 weeks and 5 umol/kg of sodium selenite was injected intraperitoneally. In exercise group, selenium group, and combination group, the mitohondrial biogenesis-related genes, including PGC-$1{\alpha}$, NRF-1, and Tfam expression level were significantly increased compared to control group. Consistent with the increased biogenesis-related genes, the cytochrome C in the treated groups, which was the indicator of mitochondrial content, was significantly increased compared to control group. Especially, combination of exercise and selenium may be effective in the increase of mitochondrial biogenesis, activity and insulin sensitivity. Therefore, exercise and selenium treatment is likely to promote diabeticmitochondrial malfunction and then improve diabetes.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.9
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• pp.1020-1026
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• 2007

The control of pathogenic microorganisms is important issue in human environments, especially in surface area. However, surface disinfection has not been fully researched. In this study, the surface disinfection under UV irradiation was performed to investigate the quantitative kinetics for Bacillus subtilis spore inactivation in several experimental conditions, such as light intensity, temperature and surface roughness. This study reports that UV light would apparently inactivates the microorganisms and the required IT value for 2 log (99%) Bacillus subtilis spore inactivation was found to be 14.5 $mJ/cm^2$ in plain surface, as predicted by the Delayed Chick-Watson model. When UV was irradiated, there were no significant temperature effects. However, the experimental result shows that the more increased IT values are required at larger surface roughness.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.3
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• pp.347-355
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• 2006

Anyang Stream including its main branch is the biggest branch stream of Han River in Korea. The geological and geomorphological characteristics were investigated to the affected area of Anyang Stream, in which rainfall characteristic was analyzed. The water quality surveyed that the analysis of water pollution used to biotic index and biological water pollution. The rainfall pattern in this area was like to that of typical Korea, but the rate of trigger and runoff during summer season(June~August) is more higher than mean of Korea. Before 2003, a dried stream is severe status, which was due to abundant runoff, but this status are improved. After 1997, water quality of stream is recovering status such as water pollution of stream steeply decreased. Especially after 2003, this trend is more quickly improved. Although, owing to the increasing of a T-N and SS at upstream wastewater were due to bad collection of industrial factories, livestock's and mans living, the water quality worsted at upstream. Water quality in total section of main stream was severely contaminated that water-quality limit is 5 with polysaprobic by water self-purification. That of main branch was 1~3limits with ${\alpha}$- and ${\beta}$-mesosaprobic in Anyang city area, But water quality in all area about another branch of Anyang stream except Anyang city area was almost under of 3 grades. Though trying of Anyang city for recover movement(completion of 2nd Sewage Treatment Plant and Water supply pipe system) on Anyang stream, water pollution states of upper branch in Anyang stream was not better than its of 2002 because it may be difference of control area on other cities.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.4
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• pp.229-233
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• 2007

A long-term rice paddy field, which is located in the National Institute of Crop Science (Suwon city, Korea) has been managed for studying of fertilization and composting impact on paddy soil fertility since 1954. The objective of this research was to evaluate soil quality through dehydrogenase analysis in long-term paddy soil treatment plots, such as control, N fertilization (N), NPK fertilization (NPK), and rice straw compost with NPK (CNPK). Dehydrogenase-producing bacterial population developing red-colored triphenyl formazan (TPF) was highly correlated to the dehydrogenase activity in rice paddy soils sampled prior to waterlog. The dehydrogenase-producing bacterial population and dehydrogenase activity was comparatively high in plots of NPK, and CNPK, which organic matter content was relatively high.