• Economic and Environmental Geology
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• v.17 no.4
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• pp.315-320
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• 1984

The newly discovered minerals found during 30 years have been discovered with election microprobe analysis, and several other new minerals have been described largely on the basis of probe analysis. Widely used types of instrument are the wavelength dispersive spectrometer (WDS) and the energy dispersive Spectrometer (EDS), with emitted X-ray dispersed by a curved crystal that is arranged to satisfy the Bragg equation ($n{\lambda}=2dsin{\theta}$). Atomic Nos of Z 4 to 92 can be analyzed quantitatively if they present in amount exceeding 50~100ppm. The application of the microprobe in mineralogical and geological research is quantitative chemical analysis of grains as small as a few microns in diameter, individual grains in a rock or can be analyzed in thin section and polished section, analysis can be made comparatively short time, methods in non-destructure, to photographical and crystallographical information. This paper was written in order to document data evaluation procedure for quantitative energy dispersive election probe analysis.

• Journal of Soil and Groundwater Environment
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• v.20 no.7
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• pp.80-89
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• 2015

Nitrate is on the most seriou pollutant encountered in shallow groundwater aquifer in agricultural area. There are various remediation technologies such as ion exchange, reverse osmosis, and biological denitrification to recover from nitrate contamination. Biological denitrification by indigenous microorganism of the technologies has been reviewed and applied on nitrate contaminated groundwater. In this work, we selected the site where the annual nitrate (NO₃⁻) concentration is over 105 mg/L and evaluated denitrification process with sampled soil and groundwater from 3 monitoring wells (MW4, 5, 6). In the results, the nitrate degradation rate in each well (MW 4, 5, and 6) was 25 NO₃⁻ mg/L/day, 6 NO₃⁻ mg/L/day, and 3.4 NO₃⁻ mg/L/day, respectively. Nitrate degradation rate was higher in batch system treated with 2 times higher fumarate as carbon source than control batch system (0.42M fumrate/1M NO₃⁻), comparing with batch system with soil sample. This result indicates that increase of carbon source is more efficient to enhance denitrification rate than addition of soil sample to increase microbial dynamics. In this work, we also confirmed that monitoring method of functional genes (nirK and nosZ) involved in denitrification process can be applied to evaluated denitrifcation process possibility before application of field process such as in-situ denitrification by push-pull test.

• Microbiology and Biotechnology Letters
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• v.47 no.4
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• pp.630-638
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• 2019

Nitrous oxide (N₂O) is a greenhouse gas with a global warming potential 310 times higher than that of carbon dioxide. In this study, an N₂O-reducing consortium was obtained by enrichment culture using advanced treatment sludge as the inoculum. The dominant bacteria in the consortium were Sulfurovum (17.95%), Geobacter (14.63%), Rectinema (11.45%), and Chlorobium (8.24%). The consortium displayed optimal N₂O reducing activity when acetate was supplied as the carbon source at a carbon/nitrogen ratio (mol·mol^-1) of 6.3. The N₂O reduction rate increased with increasing N₂O concentration at less than 3,000 ppm. Kinetic analysis revealed that the maximum N₂O reduction rate of the consortium was 163.9 ㎍-N·g-VSS^-1·h^-1. Genes present in the consortium included nosZ (reduction of nitrous oxide to N₂), narG (reduction of nitrate to nitrite), nirK (reduction of nitrite to nitric oxide), and norB (reduction of nitric oxide to nitrous oxide). These results indicate that the N₂O-reducing consortium is a promising bioresource that can be used in denitrification and N₂O mitigation.

• Korean Journal of Microbiology
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• v.52 no.2
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• pp.166-174
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• 2016

In order to find an efficient bacterial strain that can carry out nitrification and denitrification simultaneously, we isolated many heterotrophic nitrifying bacteria from wastewater treatment plant. One of isolates NS13 showed high removal rate of ammonium and was identified as Alcaligenes faecalis by analysis of its 16S rDNA sequence, carbon source utilization and fatty acids composition. This bacterium could remove over 99% of ammonium in a heterotrophic medium containing 140 mg/L of ammonium at pH 6-9, $25-37^{\circ}C$ and 0-4% of salt concentrations within 2 days. It showed even higher ammonium removal at higher initial ammonium concentration in the medium. A. faecalis NS13 could also reduce nitrate and nitrous oxide by nitrate reductase and nitrous oxide reductase, respectively, which was confirmed by detection of nitrate reductase gene, napA, and nitrous oxide reducase gene, nosZ, by PCR. One of metabolic intermediate of denitrification, $N_2O$ was detected from headspace of bacterial culture. Based on analysis of all nitrogen compounds in the bacterial culture, 42.8% of initial nitrogen seemed to be lost as nitrogen gas, and 46.4% of nitrogen was assimilated into bacterial biomass which can be removed as sludge in treatment processes. This bacterium was speculated to perform heterotrophic nitrification and aerobic denitrification simultaneously, and may be utilized for N removal in wastewater treatment processes.

• Microbiology and Biotechnology Letters
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• v.48 no.1
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• pp.72-78
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• 2020

The dynamics of nitrogen compounds and RNA-based functional genes were characterized in the nitrification-denitrification coupling process. For the removal of residual ammonium, intermittent aeration was introduced in the denitrification reactor. N₂O production was not observed in both reactors. In both reactors, the nitrifying genes (achaeal-amoA, bacterial-amoA and hor) and denitrifying genes (narG, nirK, norB and nosZ) had a copy number of 3.92 × 10²-7.25 × 10⁵ and 2.85 × 10²-3.06 × 10⁴ per ng of DNA, respectively. These results suggest that denitrification and nitrification reactions occur in both the nitrification and denitrification reactors, respectively. Therefore, the coupling process is a promising one for the conversion of ammonium to nitrogen without generating N₂O.

• Korean Journal of Environmental Agriculture
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• v.42 no.4
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• pp.418-426
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• 2023

This study focused on nitrous oxide, a major greenhouse gas produced in agricultural settings through bacterial nitrogen oxidation in aerobic soil. Nitrogen fertilizer in farmland is identified as a primary source of nitrous oxide. The importance of reducing excess nitrogen in soil to mitigate nitrous oxide production is well-known. The study investigated the use of liquefied pig manure as an alternative to urea fertilizer in conventional agriculture. Results showed a more than two-fold reduction in nitrous oxide emissions in pepper cultivation areas with liquefied pig manure compared to that with urea fertilizer. The population of Nitrosospira, a nitrous oxide-producing bacterium, decreased by over 10% with liquefied pig manure. Additionally, nirK and nosZ, which are related to the denitrification process, significantly increased in the urea fertilizer group, whereas levels in the liquefied pig manure group resembled those with no nitrogen treatment. In conclusion, the experiment confirmed that liquefied pig manure can serve as an eco-friendly nitrogen fertilizer, significantly reducing nitrous oxide production, a major contributor to the atmospheric greenhouse effect.

• Journal of Plant Biotechnology
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• v.50
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• pp.27-33
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• 2023

Zizyphus jujube is a plant in the buckthorn family (Rhamnaceae) that has been the subject of research into antibacterial, antifungal and anti-inflammatory properties of its fruit and seed. However, few studies have investigated its leaves. In this study, the anti-inflammatory activity of ZJL (an extract of Z. jujube leaf) was evaluated to verify its potential as an anti-inflammatory agent and SARS-CoV-2 medicine, using nitric oxide (NO) assay, RT-PCR, SDSPAGE, Western blotting, and UHPLC/TOFHRMS analysis. We found that ZJL suppresed pro-inflammatory mediators such as NO, inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and tumor necrosis factor α (TNF-α) in lipopolysaccharide (LPS)-induced RAW264.7 cells. ZJL acted by inhibiting NF-KB and MAPK signaling pathway activity. We also confirmed that ZJL contains a phenol compound and flavonoids with anti-inflammatory activity such as trehalose, maleate, epigallocatechin, hyperoside, catechin, 3-O-coumaroylquinic acid, rhoifolin, gossypin, kaempferol 3-neohesperidoside, rutin, myricitrin, guaiaverin, quercitrin, quercetin, ursolic acid, and pheophorbide a. These findings suggest that ZJL may have great potential for the development of anti-inflammatory drugs and vaccines via inhibition of NF-κB and MAPK signaling in LPS-induced RAW264.7 cells.

• Proceedings of the Korean Society of Toxicology Conference
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• 1998.10a
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• pp.36-36
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• 1998

Tumorigenicity of benzo(a)pyrene (BP) and benzo(a)pyrene diol epoxides ((+)BPDE-1, (-)BPDE-1) was investigated in transgenic TG-AC mice carrying v-Ha-ras oncogene fused to the promoter of the mouse embryonic a-like, z-globin gene. Animals were topically treated twice per week for 25weeks with BPDE (10$\mu$g/mouse) and BP (10, 20, 40$\mu$g/mouse). In addition, animals were treated with BPDE or BP (initiated) followed by TPA (2$\times$2.5$\mu$g/week, for 4 weeks) for promotion study. In the continuous treatment of BPDE or BP, animals treated with 40$\mu$g BP showed $100\%$ tumor response after 20 weeks, $40\%$ of mice for 20$\mu$g BP, and $20\%$ for (+)BPDE-1, but (-)BPDE-1 and 10$\mu$g BP did not show any tumor response. After 25 weeks, most tumors turned out to be carcinomas in animals treated with 40$\mu$g BP. In BPDE or BP/TPA Initiation-promotion study, papilloma response occurred earlier (6 weeks after TPA treatment) than in continuously treated animals with BPDE or BP. RT-PCR assay for transgene expression showed that BP or BPOE was not transgene dependent in its tumorigenicity, but TPA was. Several Cytokine genes(TGF-a, TNF-a) and c-myc gene expressions were monitored in skin tissues during BP carcinogenesis. In early stage of BP treatment, the gene expressions were elevated(c-myc,TGF-a) or unchanged(TNF-a) compared to control, but the levels were gradually decreased during both middle and late stages of cacinogenesis, Gene expression levels of skin papillomas in acetone initiated-TPA promoted animals were close to those of middle stage or between middle and late stages. i-NOS was also highly expressed in carcinoma and papilloma, These data suggest that transgene expressions of TG-AC mice were not dependent on BP carcinogenesis and that TG-AC mice were more sensitive to TPA regardless of types of initiators. In addition, genes(TGF-a, c-myc, TNF-a, i-NOS) were modulated in the skin during BP cacinogenesis or TPA promotion.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.6
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• pp.750-756
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• 2010

Two trials were conducted to study the effects of two Chinese herbal polysaccharides, Astragalus polysaccharides (APS) and Achyranthes bidentata polysaccharides (ABPS), and one Chinese herbal saponin, Acantbepanax senticosus saponin (ASS), on the immunity and growth performance of weaned pigs. Experiment 1 was a 14-day growth assay, in which 32 weaned pigs were randomly allocated to one of four dietary treatments: i) 0.05% talcum powder control; ii) 0.05% APS; iii) 0.05% mixture of APS and ASS in a 1:1 ratio by weight; and iv) 0.05% mixture of APS, ASS, and ABPS in a ratio of 1:1:1 by weight. Blood samples were collected on day 14 to determine plasma parameters. Feed intake, body weight gain, and feed efficiency were also determined. Experiment 2 was a 21-day immunity assay, in which 16 weaned pigs were randomly allotted to one of two dietary treatments: i) 0.05% talcum powder control; and ii) 0.05% mixture of APS and ASS in a 1:1 ratio by weight. On day 21, pigs were challenged with lipopolysaccharide (LPS) and 3 h later blood samples were collected and analyzed for lymphocyte proliferation as well as interleukin 6 (IL-6), insulin-like growth factor 1 (IGF-1), growth hormone (GH), and cortisol levels. In Experiment 1, feeding Chinese herbal polysaccharides and saponin increased growth performance of the pigs. The effects of the mixture of APS and ASS were especially notable, as there was a significant improvement in growth performance compared with the control (p<0.05). The plasma concentration of immunoglobulin G (IgG), nitric oxide (NO), and nitric oxide synthase (NOS) were increased in all treatments groups, with the mixture of APS and ASS increasing the level of IgG and NOS significantly (p<0.05), compared with the control. There was no difference in the NO level between the control and treatment groups (p>0.05). In Experiment 2, Chinese herbal polysaccharides and saponin showed immunostimulating effects. The level of cortisol, GH, and IGF-I were significantly increased (p>0.05), and the level of IL-6 showed a significant decrease (p<0.05) in the APS and ASS treatment after the LPS challenge. The mixture of APS and ASS could stimulate the blood lymphocyte proliferation significantly whether the LPS was injected or not (p<0.05). These results show that Chinese herbal extracts can improve growth performance and stimulate immunity of weaned pigs. A mixture of APS and ASS, compared with APS alone, could be a new kind of immunostimulant for weaned pigs, which could result in greater positive effects on their growth performance and immunity.

• Restorative Dentistry and Endodontics
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• v.19 no.2
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• pp.585-601
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• 1994

The purpose of this study was to evaluate the ability of several intracoronal base materials to prevent cervical leakage of a bleaching agent into the dentinal tubules and along the root canal. In this study, thirty-two anterior teeth were used. After lingual access was prepared in each tooth, tooth was instrumented with a step-back technique to a Nos. 40-50 using K-type files. All teeth were obturated with a lateral condensation technique. Excess gutta percha was removed with a warm instrument to the facial level of the CEJ. Teeth were divided into four groups : Teeth in control group were not filled with base material. Teeth in groups 1, 2, and 3 had 2mm of gutta percha removed with a warm instrument, then Dycal, Fuki II LC and Z-100 were filled with palstic instruments on the top of the gutta percha respectively. All teeth were bleached for 7 days, fresh bleach was added for another 7 days, then a 10 % methylene blue dye was placed inside the access preparation. They were stored at $37^{\circ}C$ and $100^{\circ}C$ humidity for 5 days. Each tooth was sectioned perpendicular to the long axis using a diamond disk. Initial cuts were made at the most coronal level of facial and lingual CEJ's, then another cuts continued appically in the levels of 0.5mm, 1.5mm, and 2.0mm respectively. The amount of dye leakage through the dentinal tubules was determined at each cut section. In addition, when the cut specimen was determined to be last penetration of any dye, this level was recorded as depth of apical leakage from the coronal terminus of the gutta percha, Dycal, Fuji II LC and Z-100. The acquired data were analyzed by Tukey's Multiple Range Test adn Cochran-Mantel-Haenszel Test to see if there was any statistically significant difference in dye penetration and linear apical leakage among the groups. The results were as follows : 1. Control group at levels of CEJ and 0.5mm, group 3 at level of 1.5mm, and group 2 AND 3 at level of 2.0mm showed the least dye penetration through the facial or lingual dentinal tubules, but there were no significant difference among three groups. 2. Group 2 at levels of CEJ and 0.5mm, group 3 at level of 1.5mm, and group 2 and 3 at level of 2.0mm showed the least dye penetration through the proximal dentinal tubules, but there were no significant difference among control group, group 2, and group 3. 3. Group 1 showed the greatest dye penetration through the facial or lingual and proximal dentinal tubules at all levels, and there were significant difference with other three groups. 4. Control group and group 1 showed 2mm apical dye leakage at facial or lingual and proximal aspects, group 2 showed 1.5mm, and group 3 showed 0.5mm.