• Korean Journal of Soil Science and Fertilizer
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• v.40 no.5
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• pp.418-428
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• 2007

Physical and chemical properties of the aggregate by-products including sludge and crushed dust samples collected from the 21 private companies throughout the country were analyzed to evaluate possible usage of the by-products as artificial soil materials for plantation. The pH of the materials ranged from 8.0 to 11.0. The organic matter content was $2.85g\;kg^{-1}$, and the total nitrogen content and available phosphate content were low as 0.7 percents and $12.98mg\;kg^{-1}$, respectively. Exchangeable $Ca^{2+}$, $Mg^{2+}$, $K^+$, and $Na^+$ were 2.29, 0.47, 0.02 and $0.05cmol\;kg^{-1}$, respectively. Heavy metal contents were lower than the limits regulated by environmental law of Korea. Textural analysis showed that most of the materials were silt loam with low water holding capacity ranged from 0.67 to 7.41 percents, and with low hydraulic conductivity ranged from 0.4 to $2.8m\;s^{-1}$. Mineralogical analysis showed that the aggregate by product materials were mostly composed of silicate, alumina and ferric oxides except calcium oxide dominant materials derived from limestones. The primary minerals were quartz, feldspars and dolomites derived from granite and granitic gneiss materials. Some samples derived from limestone material showed calcite and graphite together with the above minerals. According to the result, it can be concluded that the materials could be used as the artificial soil material for plantation after proper improvement of the physico-chemical properties and fertility.

• Tuberculosis and Respiratory Diseases
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• v.46 no.1
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• pp.44-52
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• 1999

Background : Airway infiltration by inflammatory cells, particularly of eosinophils, is one of the characteristic features of asthma. Several mechanisms for the recruitment of eosinophil is focused on the CD4+ T lymphocyte for the preferential production of Th2-c1erived cytokines. Interleukin-10(IL-10) is identified cytokine with potent antiinflammatory activity. This molecule has been shown to inhibit the release of cytokine from inflammatory cells including Th2 cell, and also to inhibit eosinophil survival. We therefore attempted to determine whether decreased synthesis of IL-10 in the lung of bronchial asthma may contribute to inflammation that is characteristics of this dease. Method: Subjects were patients with bronchial asthma(n=23) and normal controls(n=11). IL-10 produced from peripheral mononuclear cell(PBMC) and in bronchoalveolar lavage(BAL) fluid was measured by ELISA method. Degree of bronchial inflammation was assessed by total cell counts and eosinophil percents in BAL fluid, eosinophil infiltration on bronchial biopsy tissue and $PC_{20}$ for methacholine. Results: The IL-10 level produced by PBMC and in BAL fluid from patient with bronchial asthma were not different with normal controls(respectively, $901.6\pm220.4$ pg/ml, $810.9\pm290.8$ pg/ml for PBMC, $24.5\pm9.5$ pg/mL $30.5\pm13.5$ pg/ml for BAL fluid p>0.05). There were significant negative correlation between IL-10 in BAL fluid and eosinophil percents in BAL fluid or degree of eosinophil infiltration in bronchial biopsy (respectively r=-0.522, r=-0.4486 p<0.05). However there was no difference of IL-10 level according to $PC_{20}$ for methacholine. There were no correlation between IL-10 production by PBMC and peripheral blood eosinophil counts or serum eosinophilic cationic protein levels(respectively r=0.1146, r=0.0769 p>0.05). Conclusion: These observation suggest that IL-10 may participate but not acts the crucial role in regulation of the airway inflammation in bronchial asthma.

• Atmosphere
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• v.32 no.1
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• pp.61-70
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• 2022

This study evaluates the economic values for the several first precipitation events during Changma period. The selected three years are 2015, 2019, and 2020, where average precipitation amounts across the 58 Korean stations are 12.8, 20.1 and 13.3 mm, respectively. The four categories are used to assess the values including air quality improvement, water resource acquisition/accumulation, drought mitigation, and forest fire prevention/recovery. Economic values for these three years are estimated 50~150 billion won. Among the four factors considered, the effect of air quality improvement is most highly valued, amounting to 70 to 90% of the total economic values. Wet decomposition of air pollution (PM₁₀, NO₂, CO, and SO₂) is the primary reason. The next valuable element is water resource acquisition, which is estimated 9~15 billion won. Effects of drought mitigation and fire prevention are deemed relatively small. This study is the first to estimate the value of the precipitation events during Changma onset. An analysis for more Changma years will be performed to achieve a more reliable estimate.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.7
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• pp.1115-1124
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• 2013

The present study was conducted to ensure the diversity of domestic solar salt by analyzing the composition and microbiological characteristics of solar salt (from Docho island: DS) and the flower of salt produced in different Korean salt flats (Sinui island: SF, Bigum island: BF, and Docho island: DF). The analyses showed that the moisture content of the three types of flower of salt and solar salt ranged from 10.54~13.82% and NaCl content ranged from 78.81~84.61%. The mineral content of those salts ranged from 3.57~5.51%. The content of insoluble matter in these salts was $0.01{\pm}0.00{\sim}0.05{\pm}0.00%$. The sand content of these salts was $0.01{\pm}0.01{\sim}0.03{\pm}0.01%$. By Hunter's color value analysis, the color of the flower of salt was brighter and whiter than solar salt. The salinity of the flower of salt was a little higher than solar salt as well. The magnesium and potassium ion content of DF was $9,886.72{\pm}104.78mg/kg$ and $2,975.23{\pm}79.73mg/kg$, respectively, which was lower than the content in SF, BF, and DS. The heavy metal content of all salts was acceptable under the Korean Food Sanitation Law. The flower of salt was confirmed to be sweeter and preferable to solar salt. More than 80% of the solar salt crystals were 2~3 mm in size, whereas crystals from the flower of salt were 0.5~2 mm in size. The bacterial diversity of DF and DS were investigated by culture and denaturing gradient gel electrophoresis (DGGE) methods. The number of cultured bacteria in flower of salt was approximately three times more than solar salt. By DGGE analysis, major microbes of DF were Maritimibacter sp., Cupriavidus sp., and unculturable bacteria, and those of DS were Cupriavidus sp., Dunalidella salina and unculturable bacteria. The results of DGGE analysis showed that major microorganisms in solar salts were composed of unidentified and unculturable bacteria and only a few microorganisms were culturable.

• Development and Reproduction
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• v.14 no.4
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• pp.297-306
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• 2010

Tributyltin (TBT), an endocrine disrupting chemical, has been reported to decrease testicular function by causing apoptosis in the testis, but this mechanism is not fully understood. Thus, in this study we examined whether TBT induces adipogenesis of the Leydig cells to find out the correlation between adipogenesis and apoptosis in the testis. Three week old SD male rats were orally administrated with sesame oil, 1 mg/kg of TBT, or 10 mg/kg of TBT daily for 1 week and weighed after administration. The testes obtained on day 8 were weighed and stained with BODIPY and TUNEL kit. Using total RNA extracted from the isolated Leydig cells, adipogenesis and apoptosis-related genes were analyzed by real-time PCR. The testicular weights of the rats treated with 10 mg/kg TBT were significantly decreased compared to those in the control rats treated with sesame oil. As a result of BODIPY staining, the number of Leydig cells stained with BODIPY was increased in the rats treated with 10 mg/kg TBT compared with the control rats. Similar to BODIPY staining results, the TUNEL assay showed that the apoptosis of Leydig cells was increased in TBT treated rats. The results of the gene expression analysis in the Leydig cells showed that the expression of adipogenesis-related genes (PPAR${\gamma}$, aP2, Perilipin, CD36) and apoptosis-related genes (TNFRSF1A, TNFSF10) was increased after TBT administration. The present study demonstrates that TBT induces the expression of adipogenesis-related and apoptosis-related genes in the Leydig cells leading to adipogenesis and apoptosis in the testes. These results suggest that the dysfunction of Leydig cells by TBT exposure may cause a loss in testicular function.