• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.8
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• pp.627-633
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• 2019

Rapid and accurate identification of marine microalgae causing harmful algal blooms (HABs) is a crucial tool for predicting and managing HABs. We previously developed a nuclease protection assay sandwich hybridization (NPA-SH) method for the in situ detection of blooming microalgae Cochlodinium polykrikoides. In this study, we improved the applicability of the NPA-SH method for the detection of C. polykrikoides by simplifying the reaction step. For this purpose, invertase (INV) was conjugated to the signal probe instead of using fluorescence, and sucrose was used as a reactant to induce a color reaction. The INV-signal probe conjugation was confirmed by SDS-PAGE and epifluoromicroscopy. The treatment time and appropriate amounts of the probe and sucrose that optimized the reaction were determined. As a result, the developed INV-SH reduced the treatment time in the field compared with NPA-SH, and also enabled the use of a relatively small volume and low-priced personal glucose meter, as well as an absorbance meter. INV-SH is the first C. polykrikoides species identification technology to which INV has been applied and could be an improved field technique.

• Journal of Korean Society on Water Environment
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• v.21 no.5
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• pp.477-483
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• 2005

Anammox (Anaerobic Ammonium Oxidation) bacteria is recently discovered microorganism which can oxidize ammonium to nitrogen gas in the presence of nitrite under anaerobic conditions. The anammox process can save an energy for nitrification and need not require a carbon source for denitrification, however, the start-up periods takes a long time more than several months due to the long doubling time (approximately 11 days). In order to find the effects of seeding microorganisms, hydrazine, and nitrite concentration on the enhancement of the anammox activity, five kinds of microorganisms were selected. Among the several kinds of seeding microorganisms, the granule from acclimated microorganisms treating high concentration of ammonia nitrogen (A-1) and sludge from piggery wastewater treatment plant (A-2) were found to have a high anammox activity. In the case of A-1, the maximum nitrogen conversion rate represented 0.4 mg N/L-hr, and the amount of nitrite utilization was high compared to those of other seeding microorganisms. The A-4 represented a higher nitrogen conversion rate to 0.7 mg N/L-hr although the ammonium concentration in the serum bottle was high as 200 mg/L. Meanwhile, the anaerobic granule from UASB reactor treating distillery wastewater showed a low anammox activity due to the denitrification by the remained carbon sources in the granule. Hydrazine, intermediate product in anammox reaction, enhanced the anammox activity by representing 1.4 times of nitrogen gas was produced in the test bottle than that of control, when 0.4 mM of $N_2H_4$ was added to serum bottle which contains 5 mM of nitrite. The high concentration of nitrite (10 mM) resulted in the decrease of the anammox activity by showing lower production of nitrogen gas compared to that of 5 mM addition of nitrite concentration. As a result of FISH (Florescence In-Situ Hybridization) experiment, the Amx820 probe showed a more than 13% of anammox bacteria in a granule (A-1).

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.5
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• pp.650-657
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• 2018

Objective: The study investigated the biological functions and mechanisms for controlling cashmere growth of Liaoning cashmere goat by ovarian carcinoma immunoreactive antigen-like protein 2 (OCIAD2) and decorin (DCN) genes. Methods: cDNA library of Liaoning cashmere goat was constructed in early stages. OCIAD2 and DCN genes related to cashmere growth were identified by homology analysis comparison. The expression location of OCIAD2 and DCN genes in primary and secondary hair follicles (SF) was performed using in situ hybridization. The expression of OCIAD2 and DCN genes in primary and SF was performed using real-time polymerase chain reaction (PCR). Results: In situ hybridization revealed that OCIAD2 and DCN were expressed in the inner root sheath of Liaoning cashmere goat hair follicles. Real-time quantitative PCR showed that these genes were highly expressed in SF during anagen, while these genes were highly expressed in primary hair follicle in catagen phase. Melatonin (MT) inhibited the expression of OCIAD2 and promoted the expression of DCN. Insulin-like growth factors-1 (IGF-1) inhibited the expression of OCIAD2 and DCN, while fibroblast growth factors 5 (FGF5) promoted the expression of these genes. MT and IGF-1 promoted OCIAD2 synergistically, while MT and FGF5 inhibited the genes simultaneously. MT+IGF-1/MT+FGF5 inhibited DCN gene. RNAi technology showed that OCIAD2 expression was promoted, while that of DCN was inhibited. Conclusion: Activation of bone morphogenetic protein (BMP) signaling pathway up-regulated OCIAD2 expression and stimulated SF to control cell proliferation. DCN gene affected hair follicle morphogenesis and periodic changes by promoting transforming growth $factor-{\beta}$ ($TGF-{\beta}$) and BMP signaling pathways. OCIAD2 and DCN genes have opposite effects on $TGF-{\beta}$ signaling pathway and inhibit each other to affect the hair growth.

• Journal of the Korean Chemical Society
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• v.66 no.3
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• pp.202-208
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• 2022

In this study, we tried to obtain the optimal conditions to reduce odors generated from pig wastewater using magnesia (MgO) through in-situ test after producing a reactor for removing odors. For this purpose, the filling amount of magnesia, the injection amount of pig wastewater, the aeration method, the aeration amount and the aeration time were considered. The field experiment was conducted at Cheongwoon Livestock Farm, which has a pig wastewater reservoir. As the amount of magnesia added to the weight of wastewater (500 kg) increases, the amount of ammonia (NH₃) and hydrogen sulfide (H₂S) generated tended to gradually decrease. As a result of the test, ammonia and hydrogen sulfide in the pig wastewater decreased up to 65% and 77%, respectively, for 2 days aeration after 0.8% of magnesia was added to the reaction tank. The initial pH of the pig wastewater in the reactor was 8.2, and the pH was found to be 9.2 when magnesia was added up to 0.8%. In the light of this trend, it can be known that magnesia gradually increases the pH in the pig wastewater and makes it weakly alkaline. As the pH increases, part of the ammonia gas present in the pig wastewater vaporizes into the air and the remaining part is removed by precipitation after chemical bonding with dissolved magnesium ions and phosphate ions. In order to remove the odor of pig wastewater and turn it into compost, most of the existing livestock farms go through a six-month aeration process using microorganisms. In contrast, the current study proved the effect of removing odors from pig wastewater within 2 days through chemical reactions that do not affect microbial activity.

• Korean Chemical Engineering Research
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• v.47 no.5
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• pp.630-638
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• 2009

A computational fluid dynamics(CFD) model is developed and validated with on-site experiments for a urea-based SNCR(selective non-catalytic reduction) process to reduce the nitrogen oxides($NO_x$) in a municipal incinerator. The three-dimensional turbulent reacting flow CFD model having a seven global reaction mechanism under the condition of low CO concentration and 12% excess air and droplet evaporation is used for fluid dynamics simulation of the SNCR process installed in the incinerator. In this SNCR process, urea solution and atomizing air were injected into the secondary combustor, using one front nozzle and two side nozzles. The exit temperature($980^{\circ}C$) of simulation has the same value as in situ experiment one. The $NO_x$ reduction efficiencies of 57% and 59% are obtained from the experiment and CFD simulation, respectively at NSR=1.8(normalized stoichiometric ratio) for the equal flow rate ratio from the three nozzles. It is observed in the CFD simulations with varying the flowrate ratio of the three nozzles that the injection of a two times larger front nozzle flowrate than the side nozzle flowrate produces 8% higher $NO_x$ reduction efficiency than the injection of the equal ratio flowrate in each nozzle.

• Journal of Periodontal and Implant Science
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• v.42 no.1
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• pp.13-19
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• 2012

Purpose: The aim of this study was to examine whether a previous peri-implantitis site can affect osseointegration, by comparing implant placement at a site where peri-implantitis was present and at a normal bone site. A second aim of this study was to identify the tissue and bone reaction after treating the contaminated implant surface to determine the optimal treatment for peri-implant diseases. Methods: A peri-implant mucositis model for dogs was prepared to determine the optimal treatment option for peri-implant mucositis or peri-implantitis. The implants were inserted partially to a length of 6 mm. The upper 4 mm part of the dental implants was exposed to the oral environment. Simple exposure for 2 weeks contaminated the implant surface. After 2 weeks, the implants were divided into three groups: untreated, swabbed with saline, and swabbed with $H_2O_2$. Three implants from each group were placed to the full length in the same spot. The other three implants were placed fully into newly prepared bone. After eight weeks of healing, the animals were sacrificed. Ground sections, representing the mid-buccal-lingual plane, were prepared for histological analysis. The analysis was evaluated clinically and histometrically. Results: The untreated implants and $H_2O_2$-swabbed implants showed gingival inflammation. Only the saline-swabbed implant group showed re-osseointegration and no gingival inflammation. There was no difference in regeneration height or bone-to-implant contact between in situ implant placement and implant placement in the new bone site. Conclusions: It can be concluded that cleaning with saline may be effective in implant decontamination. After implant surface decontamination, implant installation in a previous peri-implant diseased site may not interfere with osseointegration.

• Korean Journal of Materials Research
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• v.9 no.6
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• pp.577-582
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• 1999

In order to make the electroconductive $Si_3N_4$-TiN composities, the Si-Ti(N) compacts were nitrided at $1450^{\circ}C$ for 20hours, and then they were post-sintered by a gas-pressure-sintering technique at 1TEX>$1950^{\circ}C$ for 3.5 hours. As starting powders, commercial si powder of about $10\mu\textrm{m}$, two types of Ti powders of 100 and 325 mesh, and fine-sized TiN of $2.5\mu\textrm{m}$ powders were used. In the $Si_3N_4$-TiN sintered bodies used Ti powders, the relative density and fracture strength and electrical conductivity are low due to the existence of large amounts of coarse pores. However, in the $Si_3N_4$-TiN composite used TiN powder, the fracture toughness, fracture strength and electrical resistivity were $5.0MPa{\cdot}m^{1/2}$, 624MPa and $1400{\omega}cm$, respectively. The dispersion of TiN particles in the composite inhibited the growth of $Si_3N_4$ in the shape of rod and made strong strain field contrasts at the $Si_3N_4$-TiNinterfaces. It was recognized that microstructural control is required to improve the electrical conductivity and mechanical properties of $Si_3N_4$-TiN composites by dispersing TiN particles homogeneously.

• Journal of Oral Medicine and Pain
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• v.38 no.4
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• pp.291-298
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• 2013

On this study, we treated rats with restraint stress, and observed the changes with an optical microscope. Within the salivary gland tissue, we measured cell apoptosis cycle evaluation which show positive reaction on TUNEL assay, and compared within the groups. For this study, 18 rats were divided into 3 groups; 1) 2 rats of group I were selected as a normal control. 2) 2 rats of group II, as a experimental control were placed in the restraint cone for 2 hours 3) 14 rats of group III were placed in the restraint cone for 2 hours once a day. The rats were sacrificed immediately (group II, as a experimental control), 1, 2, 3, 4, 5, 6 and 7days after application of the stress and the both parotid glands were excised. The conclusions follow. 1. 5 days after giving an confining stress to the parotid gland of Rats, we can observe the hypotropy and pus and inflammation of Rat parotid gland acinar cells, and after 7 days, we can see a cell apoptosis. 2. Through the In situ DNA end labeling assay and TUNEL dye, on serous glands, benign tumor cell increased with statistically significant result after 5 days from confining stress. And the index shows maximum value on 7th days, which is same result with histological opinion. Therefore, our study shows that a cell apoptosis can be induced by restraint stress on salivary gland tissue, and we think more study should be accomplished about the cell signaling pathway in the future.

• Korean Chemical Engineering Research
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• v.50 no.1
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• pp.50-54
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• 2012

In this study, PANI and PANI/$TiO_2$ composites were prepared as electrode materials for a supercapacitor application. Cyclic voltammetry (CV) was performed to investigate the supercapacity properties of these electrodes in an electrolyte solution of 6 M KOH. The PANI/$TiO_2$ composites were polymerized by amount of various ratios through a simple in-situ method. The morphological properties of composites were analyzed by SEM and TEM method. The crystallinity of the composite and $TiO_2$ particle size were identified using X-ray diffraction (XRD). In the electrochemical test, The electrode containing 10 wt% $TiO_2$ content against aniline units showed the highest specific capacitance (626 $Fg^{-1}$) and delivered a capacitance of 286 $Fg^{-1}$ reversibly at a 100 $mVs^{-1}$ rate. According to the surface morphology, the increased capacitance was related to the fact that nano-sized $TiO_2$ particles (~6.5 nm) were uniformly connected for easy charge transfer and an enhanced surface area for capacitance reaction of $TiO_2$ itself.

• Journal of Soil and Groundwater Environment
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• v.10 no.2
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• pp.35-43
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• 2005

Bioslurping combines the three remedial approaches of bioventing, vacuum-enhanced free-product recovery, and soil vapor extraction. Bioslurping is less effective in tight (low-permeability) soils. The greatest limitation to air permeability is excessive soil moisture. Optimum soil moisture is very soil-specific. Too much moisture can reduce air permeability of the soil and decrease its oxygen transfer capability. Too little moisture will inhibit microbial activity. So Modified Fenton reaction as chemical treatment which can overcome the weakness of Bioslurping was experimented for simultaneous treatment. Although the diesel removal efficiency of SVE process increased in proportion to applied vacuum pressure, SVE process was difficulty to remediation quickly semi- or non-volatile compounds absorbed soil strongly. And SVE process had variation of efficiency with distance from the extraction well and depth a air flow form of hemisphere centering around the well. Below 0.1 % hydrogen peroxide shows the potential of using hydrogen peroxide as oxygen source but the co-oxidation of chemical and biological treatment was impossible because of the low efficiency of Modified Fenton reaction at 0.1 % (wt) hydrogen peroxide. NTA was more efficiency than EDTA as chelating agent and diesel removal efficiency of Modified Fenton reaction increased in proportion to hydrogen peroxide concentration. Hexadecane as typical aliphatic compound was removed less than Toluene as aromatic compound because of its structural stability in Modified Fenton reaction. What minimum 10% hydrogen peroxide concentration has good remediation efficiency of diesel contaminated groundwater may show the potential use of Modified Fenton reaction after bioslurping treatment.