• Economic and Environmental Geology
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• v.56 no.1
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• pp.55-63
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• 2023

Variations in geochemical and mineralogical properties of the ferromanganese(Fe-Mn) crust reflect environmental changes. In the present study, geochemical and mineralogical analyses, including micro X-ray fluorescence and X-ray diffraction, were utilized to reconstruct the paleo-ocean environment of western Pacific Magellan seamount cluster. Samples of the Fe-Mn crust were collected using an epibenthic sledge from the open seamount XX (151° 51.12' 7.2" E and 16° 8.16' 9.6" N, 1557 meters below sea level) in the Western Pacific Magellan Seamount. According to the structure and phosphating status, the Fe-Mn crust of the OSM-XX can be divided into the following: phosphatizated (L4-L5), massive non-phosphatizated (L3), and porous non-phosphatizated (L1-L2) portions. All ferromanganese layers contain vernadite, and owing to the presence of carbonate fluorapatite (CFA), the phosphatizated portion (L4-L5) is rich in Ca and P. The massive non-phosphatizated section (L3) contains high Mn, Ni, and Co, whereas the porous non-phosphatizated portion (L1-L2), which comprises detrital quartz and feldspar, is rich in Fe. Variations in properties of the Fe-Mn crust from the OSM-XX reflect changes in the nearby marine environment. The formation of this crust started at approximately 51.87 Ma, and precipitation of the CFA during the global phosphatization event that occurred at approximately 36-32 Ma highlights an elevated sea level and low temperature during the associated period. The high Mn, Ni, and Co concentrations and elevated Mn/Fe ratios of samples from the massive phosphatizated portion indicate that the oxygen minimum zone (OMZ) was enhanced, and reducing conditions prevailed during the crust formation. The high Fe and low Mn/Fe ratios in the porous portion indicate a weak OMZ and dominantly oxidizing conditions. These data reflect environmental changes following the end of the Mi-1 glacial period in the Miocene-Oligocene boundary. Subsequently, Mn/Fe and Co/Mn ratios increased slightly in the outermost part of Fe-Mn crust because of the enhanced bottom current and OMZ associated with the continued cooling from approximately 9 Ma. However, the reduced carbonate dissolution rate in the Pacific Ocean from approximately 6 Ma decreased the growth rate of the Fe-Mn crust.

• Journal of Korean Society of Forest Science
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• v.85 no.4
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• pp.634-646
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• 1996

This study was carried out to reveal the forest land effect on water purification in mountainous watersheds. Rainfall, throughfall, stemflow, soil and stream water were monitored by pH, electrical conductivity(EC), and dissolved oxygen(DO) in Daehan-Ri and Parkdal-Ri catchments. The results were summarized as follows; 1. Rainfall pH values of Parkdal-Ri and Daehan-Ri were 7.6 and 6.4, respectively. 2. Comparing stemflow and throughfall of Pinus densiflora with Pinus rigida, the pH values of Pinus densiflora were 4.32 and 4.22 and the pH of Pinus rigida were 3.34 and 4.81, respectively. The EC values of Pinus densiflora were $119.7{\mu}S/cm$ and $96.8{\mu}S/cm$ and EC of Pinus rigida were $230.0{\mu}S/cm$ and $82.0{\mu}S/cm$. 3. All pH values were decreased as the streamflow increased except long-term runoff in Daehan-Ri. The EC values also were increased as the streamflow increased, but EC of short-term runoff in Daehan-Ri was gradually decreased as the streamflow increased due to entrance of throughfall which has high EC values at the beginning of rainfall events. The DO concentrations of all experimental plots were elevated as the streamflow increased, because reaeration occurs at the surface of the stream as the increased discharge make turbulence. 4. pH of Stemflow and throughfall in Pinus densiflora were lower than in Quercus acutissima, but EC values were higher in Pinus densiflora. 5. Water purification was mostly influenced by forest soil in forest hydrological processes. 6. Stemflow and throughfall were more influenced by dry deposition and organic acid in crown and bark than those of wet deposition. During the stemflow and throughfall passed forest soil, these acidic stemflow and throughfall were neutralized, and stream water quality was neutral or slightly alkaline.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.9
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• pp.1035-1043
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• 2007

A leachate containing an elevated concentration of organic and inorganic compounds has the potential to contaminate adjacent soils and groundwater as well as downgradient areas of the watershed. Moreover high-strength ammonium concentrations in leachate can be toxic to aquatic ecological systems as well as consuming dissolved oxygen, due to ammonium oxidation, and thereby causing eutrophication of the watershed. In response to these concerns landfill stabilization and leachate treatment are required to reduce contaminant loading sand minimize effects on the environment. Compared with other treatment technologies, leachate recirculation technology is most effective for the pre-treatment of leachate and the acceleration of waste stabilization processes in a landfill. However, leachate recirculation that accelerates the decomposition of readily degradable organic matter might also be generating high-strength ammonium in the leachate. Since most landfill leachate having high concentrations of nitrogen also contain insufficient quantities of the organic carbon required for complete denitrification, we combined a shortcut biological nitrogen removal (SBNR) technology in order to solve the problem associated with the inability to denitrify the oxidized ammonium due to the lack of carbon sources. The accumulation of nitrite was successfully achieved at a 0.8 ratio of $NO_2^{-}-N/NO_x-N$ in an on-site reactor of the sequencing batch reactor (SBR) type that had operated for six hours in an aeration phase. The $NO_x$-N ratio in leachate produced following SBR treatment was reduced in the landfill and the denitrification mechanism is implied sulfur-based autotrophic denitrification and/or heterotrophic denitrification. The combined leachate recirculation with SBNR proved an effective technology for landfill stabilization and nitrogen removal in leachate.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.29 no.5
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• pp.272-281
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• 2003

Nontraditional or alternative medicine is becoming an increasingly attractive approach for the treatment of various inflammatory disorders and cancers. Curcumin is the major constitute of turmoric powder extracted from the rhizomes of the plant Curcuma longa. Resveratrol is a phytoalexin present in grapes and a variety of medicinal plants. In this report, We investigated the effect of curcumin and resveratrol on regulatory protein of cell cycle, induction of apoptosis and MMP activity. Treatment with 75 M curcumin for 24 hrs produced morphological changing in HN-4 cells. Curcumin and resveratrol inhibited the cellular growth in HN-4 cells. Inhibition of cell growth was associated with down-regulation of cell cycle regulatory proteins. Curcumin-induced caspase-3 activation and Bax degradation were dose-dependent with a maximal effect at a concentration of 100 M. The elevated caspase-3 activity in curcumin treated HN-4 cells are correlated with down-regulation of survivin and cIAP1, but not cIAP2. Curcumin induced a dose-dependent increase of cytochrome c in the cytosol. Curcumin induced-apoptosis was mediated through the release of cytochrome c. In addition, curcumin-induced apoptosis was caused by the generation of reactive oxygen species, which was prevented by antioxidant N-acetyl-cysteine (NAC). Cotreatment with NAC markedly prevented cytochrome c release, Bax cleavage and cell death. Also resveratrol-induced apoptosis was preceded by down-regulation of the anti-apoptotic Bcl-2, cIAP1, and caspase-3 activity. However, resveratrol-induced apoptosis was not prevented by antioxidant NAC. In addition, HN-4 cells release basal levels of MMP2 when cultured in serum-free medium. Treatment of the cells with various concentrations of PMA for 24 hr induced the expression and secretion of latent MMP9 as determined by gelatin zymography. HN-4 cells were treated with various concentrations of curcumin and resveratrol in the presence of 75 nM PMA, and MMP2 and 9 activities were inhibited by curcumin and resveratrol. These findings have implications for developing curcumin-based anticancer and anti-inflammation therapies.

• Clinical and Experimental Pediatrics
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• v.51 no.8
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• pp.868-873
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• 2008

Purpose : Immunotherapy is accepted as the only treatment of allergic disease that can modify the natural course of the disease and ameliorate symptoms. This study aimed to evaluate the safety and efficacy of ultra-rush therapy using Dermatophagoides extracts in children. Methods : Of children older than four years who had visited Bundang CHA Pediatric Allergy Clinic, those showing positive reactions only to Dermatophagoides in the skin prick test and to the nasal provocation test were included. In all, 11 and 12 patients respectively preferred conventional and ultra-rush immunotherapy. We elevated allergen concentrations diluted to 1,000:1 of the end strength by 2-3 times with 30-minute intervals and checked oxygen saturation, pulse rate, blood pressure, and systemic reactions every 15 minutes. Immunotherapy effectiveness was valued by changes in nasal provocation test scores before and after immunotherapy. Results : The average ages of patients in the conventional and ultra-rush immunotherapy groups were $8.3{\pm}2.3$ and $9.2{\pm}2.8years$, respectively. Systemic reactions were observed in six in the ultra-rush group (50%) without anaphylaxis and one (9%) in the conventional group. The average scores in the nasal provocation test before and after treatment in the conventional group were $8.2{\pm}1.5$ and $4.6{\pm}2.1$, respectively (P=0.043). In the ultra-rush immunotherapy group, the scores changed from $6.2{\pm}2.2$ to $3.7{\pm}2.5$ (P=0.017). Conclusion : Ultra-rush immunotherapy using Dermatophagoides in children is effective for treating allergic disease but can induce systemic effects rather than conventional immunotherapy.