• Korean Journal of Soil Science and Fertilizer
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• v.50 no.5
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• pp.434-451
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• 2017

For this study, groundwater samples for 3 years from 2011 through 2013 were collected at 106 groundwater monitoring site in Korea. These groundwater samples were analyzed for 13 pesticides such as cabofuran, pentachlorobenzene, hexachlorobenzene, simazine, atrazine, lindane (gamma-HCH), alachlor, heptachlor, chlordane (total), endosulfan (1, 2), dieldrin, endrin, 4,4-DDT. The objectives of this study were to determine the detection frequency and their concentrations of 13 pesticides and evaluate the health risk level considering ingestion, inhalation, and skin contact using concentrations of 13 pesticides in groundwater samples. An analysis was used for the simultaneous determination for 13 pesticides using GC-MS. GC-MS was performed on HP-5ms, using helium ($1ml\;min^{-1}$) as carrier gas. The average recoveries of the pesticides were from 92.8% to 120.8%. The limits of detection (LODs) were between $0.004{\mu}g\;L^{-1}$ and $0.118{\mu}g\;L^{-1}$ and the limits of quantification (LOQs) were between $0.012{\mu}g\;L^{-1}$ and $0.354{\mu}g\;L^{-1}$. 106 groundwater wells were selected. 54 wells were from well to monitor background groundwater quality and 52 wells were from well to monitor groundwater quality in industrial or contamination source area. Eight pesticides including pentachlorobenzene, lindane (Gamma-HCH), heptachlor, chlordane (total), Endosulfan (1, 2), dieldrin, endrin, and 4,4-DDT were not detected in groundwater samples. The detection frequency for hexachlorobenzene, alachlor, carbofuran and simazine was 23.4%, 11.4%, 7.3%, and 1.0%, respectively. Atrazine was detected once in 2011. The average concentrations were $0.00423{\mu}g\;L^{-1}$ for carbofuran, $0.000243{\mu}g\;L^{-1}$ for alachlor, $0.00015{\mu}g\;L^{-1}$ for simazine, and $0.00001{\mu}g\;L^{-1}$ for hexachlorobenzene. The detection frequency of hexachlorobenzene was high, but the average concentration was low. In the contaminated groundwater, the detection frequency for hexachlorobenzene, alachlor, carbofuran, simazine and atrazine was 26.1%, 21.3%, 7.1%, 1.9% and 0.3%, respectively. In the uncontaminated groundwater, detection frequency for hexachlorobenzene, carbofuran and alachlor were 20.2%, 7.5%, and 1.9% respectively. Simazine and atrazine were not detected at uncontaminated groundwater wells. According to the purpose of groundwater use, atrazine was detected for agricultural groundwater use. Hexachlorobenzene showed high detection frequency at agricultural groundwater use area where the animal feeding area and golf course area were located. Alachlor showed more than 50% detection frequency at cropping area, pollution concern river area, and golf course area. Atrazine was detected in agricultural water use area. By land use, the maximum detection frequency of alachlor was found near an orchard. For human risk assessment, the cancer risk for the 5 pesticides was between $10^{-7}$ and $10^{-10}$, while the non-cancer risk (HQ value) was between $10^{-4}$ and $10^{-6}$. For conclusion, these monitoring study needs to continue because of the possibility of groundwater contamination based on various purpose of groundwater use.

• Clean Technology
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• v.18 no.4
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• pp.390-397
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• 2012

Removal characteristics of lead-contaminated soil at the military shooting range located in the Changwon city were studied experimentally using soil washing process. As a washing solution, hydrogen chloride (HCl) concentrations of 0.001, 0.01, 0.1 and 0.2 N were used, and soil : solution ratios were 1 : 2, 1 : 3, 1 : 4, and 1 : 5. Particle diameter of contaminated soil of 4-0.075 mm, and washing period of 5, 10, 15, 20, 30, 60, and 120 min were used as operating parameters. The optimum concentration of HCl solution was 0.1 N (56.3% of Pb removal efficiency) with 15 minutes operation period in views of economics, and the optimum soil : solution ratio was determined as 1 g : 3 mL for 69.7% of Pb removal efficiency with 0.1 N HCl and 15 minutes washing period. As washing period increased, removal efficiency was increased until 20 min of the removal efficiency of 75.3%, and then almost stable. Pb removal efficiency in soil particle diameters of 0.075 mm or more was ranged from 77.0% to 82.0%, but it was decreased to 52.8% in diameter of less than 0.075 mm. Therefore, the optimum cut-off size of the soil particle diameter was found less than 0.075 mm. Combined HCl solution and ultrasonic washing method showed better removal efficiency compared to only water or HCl washing method for particle sizes above 0.075 mm.

• Korean Journal of Agricultural Science
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• v.41 no.3
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• pp.213-220
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• 2014

This study was conducted to evaluate the effects of high n-3 or n-6 diet on free fatty acid profile and meat quality traits of pork loin. The 20 heads of commercial $Landrace{\times}Yorkshire{\times}Duroc(LYD)$ crossbreed pigs ($90.9{\pm}2.4BWkg$) were divided into four groups by added fat and oils, such as 5% tallow (Control), 5% linseed oil (T1), 5% safflower oil (T2), and mixture of linseed oil (2.5%) + safflower oil (2.5%) (T3), then reared 4 weeks. Pork loins were taken after slaughter, then sliced in 2 cm thickness and put in low-density polyethylene (LDPE) bag for analysis. T1 showed significantly high concentration of linolenic acid ($2.35{\pm}0.21%$) (p<0.05). The total amount of saturated fatty acids (SFA), mono-unsaturated fatty acids (MUFA) and poly-unsaturated fatty acid (PUFA) was significantly high in T1 ($36.05{\pm}1.18%$), C ($22.60{\pm}2.11%$) and T2 ($47.80{\pm}1.29%$), respectively (p<0.05). However, the ratio of n-6:n-3 was significantly low in T1 ($11.57{\pm}0.90$) than that of T2 ($37.56{\pm}12.51$) (p<0.05). There was no signigicant difference in lightness, redness, pH, water holding capacity and cooking loss between treatments (p>0.05). However, the yellowness of T2 was significantly higher than others (p<0.05). From those results, it was considered that feeding high n-3 and n-6 fatty acid diet to pig enables modify fatty acid profile of pork without any side effect on meat quality.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.4
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• pp.673-682
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• 2001

The use of resin composites has continued to increase over the last several years. In spite of their growing popularity, composites continue to exhibit a number of undesirable characteristics. One of the major deficiencies of composite restorative resins is their inadequate resistance to wear. Of the multitude of factors that have been associated with wear, subsurface degradation within the restoration is considered to be one. The aim of this study was to evaluate the resistance to degradation of four commercial composite resins in an alkaline solution. This solution with a high concentration of hydroxyl ions is a convenient medium for accelerated degradation of silane coupling and filler particles. The brands studies were Definite($Degussa-H\ddot{u}ls$ AG, Germany), Prodigy(Kerr, USA), Pyramid(Bisco, USA) and Synergy(Coltene, Swiss). Preweighed discs of each brand were exposed to 0.1N NaOH solution at $60^{\circ}C$. After 14 days they were removed, neutralized with HCl, washed with water and dried. Resistance to degradation was evaluated on the basis of following parameters : (a) mass loss(%)-determined from pre-and post-exposed specimen weights : (b) Si loss(ppm)-obtained from ICP-AE analysis of solution exposed to specimens; and (c) degradation $depth({\mu}m)$-measured microscopically (SEM) from polished circular sections of exposed specimens. The results were follows: 1. Mass loss of Synergy was $1.24{\pm}0.002%$, it was the highest, there was no significant difference among the materials. 2. The degree of degradation layer depth of Synergy was $107.83{\pm}2.52{\mu}m$, it was the highest, there was no significant difference among any other materials than Synergy. 3. There was no difference among the four materials in Si loss. 4. The correlation coefficient between mass loss and degradation depth was relatively high(r=0.06, p<0.05). 5. There was no coefficient correlation between Si loss and mass loss, the degree of degradation layer depth and Si loss. 6. When observed with SEM, destruction of bonding is observed between resin matrix and filler.

• Korean Journal of Plant Resources
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• v.27 no.1
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• pp.60-71
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• 2014

This study was conducted to identify the potential of rape stalk as a raw material for biorefinery process of rape flower. At first, rape stalk (RS) was immersed in distilled water (DW), acetic acid (AA), oxalic acid (OA), sulfuric acid (SA) and sodium hydroxide (SH) solutions, and the content of reducing sugars liberated from immersed RS was analyzed. Glucose, xylose, arabinose and sucrose were detected varying with the immersion type. In particular, 1% AA-immersion of RS for 72 hr was the most effective conditions to liberate glucose from RS. Secondly, the RS residues were used for elementary analysis and fabrication of fuel pellets. In addition to the solution type, concentration of immersion solutions (0%, 1%, 2%) and immersion time (24, 72, 120 hr) were used as experimental factors. The contents of nitrogen, sulfur and chlorine reduced effectively through the immersion of RS in DW, AA and OA solutions. For properties of RS-based pellets, bulk density and higher heating value of RS-based pellets greatly increased with the immersion of RS, and the qualities were much higher than those of the A-grade pellet of the EN standards. Ash content decreased remarkably through the immersion of RS, and was satisfied with the A-grade pellet standard. Durability was negatively affected by the immersion of RS, and did not reached to B-grade of the EN standard. In conclusion, acid immersion of RS can be a pretreatment method for the production of fuel pellet and bioethanol, but use of the immersed RS for the production of high-quality pellets might be restricted due to low durability of immersed-RS pellets. Therefore, further studies, such as investigation of detailed immersion conditions, fabrication of mixed pellets with wooden materials and addition of binders, are needed to resolve the problems.

• Korean Journal of Medicinal Crop Science
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• v.11 no.1
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• pp.53-61
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• 2003

Cirsium japonicum var. ussuriense were extracted with methanol and then fractionated with nhexane, EtOAc and BuOH to get active fractions. And their antioxidant and antimicrobial activities in each fraction were determined. Ethyl acetate and butanol fraction of Cirsium japonicum var. ussuriense showed strong antioxidant activities, but hexane fraction did not show any activities. But in the antimicrobial test, Ethyl acetate fraction showed strong antimicrobial activities except to Aspergillus awamori, Asperigillus niger. Especially, Ethyl acetate fraction showed the strongest activities against Bacillus subtilis. And aqueous fraction showed the strongest activities against Cladosporium herbarum, Hypocrea nigricans. This study was performed to determine the antimutagenic and cytotoxic effect of Cirsium japonicum var. ussuriense methanol extract on Salmonella typhimurium TA98, TA100 and cancer cell lines using Ames test and cytotoxicity assay, respectively. Cancer cell lines include human lung carcinoma(A549), human breast adenocarcinoma(MCF-7) and human hepatocellular carcinoma (Hep3B). Futher fractionations with hexane, ethyl acetate, butanol and water from methanol extract of Cirsium japonicum var. ussuriense were performed to obtain effective fraction, methanol extract showed 60.14% inhibition effect on the mutagenesis induced by MNNG against TA100, while 77% and 72.5% inhibition was observed on the mutagenesis induced by 4NQO against TA98 and TA100, respectively. and methanol extract showed 82.25% and 73.7% inhibitory effect on the mutagenesis induced by Trp-P-1 against TA98 and TA100, respectively. methanol extract showed the strongest effect against A549, MCF-7 and Hep3B at the same concentration compared to those of other fration.

• Korean Journal of Medicinal Crop Science
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• v.15 no.6
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• pp.405-410
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• 2007

This study was performed to investigate anticancer activities and immuno modulatory activities in the several parts of the A. mono and A. okamotoanum. The cytotoxicity of 1 $mg/m{\ell}$ of the water extracts on normal human lung cell(HEL299) was < 19.5%. The anticancer activity of all extracts were increased in over 55% against AGS (stomach adenocarcinoma), A549 (lung adenocarcinoma), Hep3B (liver adenocarcinoma, and MCF-7 (breast adenocarcinoma) cells. The growth of human immune B and T cells was improved of A. mono and A. okamotoanum in adding 1.0 $mg/m{\ell}$ concentration. The secretion of the IL-6 and $TNF-{\alpha}$ of human immune B and T cells was increased with all extracts of A. mono and A. okamotoanum. All extracts of. A. mono and A. okamotoanum increased NK cell growth. The results showed that the barks and woods extracts of A. mono and A. okamotoanum had useful biological activities. In addition, bark of A. okamotoanuim showed the highest anticancer and immune activities.

• Restorative Dentistry and Endodontics
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• v.34 no.6
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• pp.500-507
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• 2009

The purpose of this study is to compare the antibacterial effect of $Listerine^{(R)}$ on two microorganisms (P. gingivalis and E. faecalis) with various root canal irrigants (NaOCl, CHX, EDTA) and to identify possibility of using $Listerine^{(R)}$ as a root canal irrigant. Porphyromonas gingivalis ATCC 3327 and Enterococcus faecalis ATCC 29212 were used in this experiment. For the test irrigants, 0.5%, 1%, 2.5%, 5.25% NaOCl, 0.1%, 0.2%, 1%, 2% CHX, 0.5M EDTA (18.6% EDTA) and $Listerine^{(R)}$ were prepared. Distiled water was used as control. Two methods-1) Comparison of turbidity in broth and 2) Agar diffusion test-were used to determine the extent of antibacterial effect of $Listerine^{(R)}$ and to compare it with that of NaOCl, CHX, and EDTA. All solutions tested were effective against two bacterial strains compared with control (p < 0.001). Any concentration of NaOCl, CHX, and EDTA showed similarly high effectiveness against all bacterial strains. In all experiment, $Listerine^{(R)}$ showed significantly low antibacterial effect compared with the other root canal irrigants (p < 0.05). In conclusion, the results reflect remarkably low antibacterial effect of $Listerine^{(R)}$ as compared with root canal irrigants in general so it is not suitable for the root canal irrigant.

• Journal of Embryo Transfer
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• v.18 no.3
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• pp.195-201
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• 2003

This study was carried out to establish most suitable freezing condition, to evaluate the different condition of freezing and thawing rates on the viability and motility of frozen canine spermatozoa. The ejaculated semen was added to obtained 200∼400 ${\times}$ 10$^{6}$ /$m\ell$ with extender I and was cooled to 4$^{\circ}C$ over 30, 60 and 120 minutes. And then, semen was diluted with extender II containing 4, 6 and 8％(v/v) glycerol for 60 min, respectively and packaged in 0.5$m\ell$ straw, equilibrated far 30, 60 and 120 min at 4$^{\circ}C$ and cryopreserved in liquid nitrogen vapor at different distance(3, 5, 7 and 9 cm, respectively), plunged into nitrogen tank. Samples were thawed by placing straws into 27, 37, 47, 57$^{\circ}C$ water bath for 120, 20 and 12 sec, respectively. The results were as follows; 1. The survival and motility rate immediately post-thawing was significantly higher in samples frozen in 4％ glycerol than 6 or 8％ glycerol(P< 0.05). 2. According to equilibration time at 4$^{\circ}C$, the survival and motility rate immediately post-thawing was significantly higher in samples frozen after 60 min equilibration than 30 or 120 min equilibration(P<0.05). 3. Freezing in distance of 5 cm from liquid nitrogen yield better survival and motility rate than the others(3, 7 or 9 cm)(P<0.05). 4. The effect of thawing rate on sperm survival were higher when the thawing was done at 37$^{\circ}C$ for 120 sec(P<0.05).

• Microbiology and Biotechnology Letters
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• v.40 no.3
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• pp.250-260
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• 2012

In the present study, the antioxidative and antibacterial activities of Artemisia princeps Pampanini (A. princeps Pamp.) extract were investigated. The ethyl acetate fraction of A. princeps Pamp. showed the most prominent free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activity ($FSC_{50}=12.27{\mu}g/mL$). Reactive oxygen species (ROS) scavenging activities ($OSC_{50}$) of A. princeps Pamp. extract on $Fe^{3+}-EDTA/H_2O_2$ systems were investigated using a luminol-dependent chemiluminescence assay. The ethyl acetate fraction of the extract ($OSC_{50}=0.33{\mu}g/mL$) had a 5 times greater ROS scavenging activity than L-ascorbic acid ($1.50{\mu}g/mL$), known as a water soluble antioxidant. The cellular protective effects of fractions of A. princeps Pamp. on the rose-bengal sensitized photohemolysis of human erythrocytes were examined. The aglycone fraction of extracts suppressed photohemolysis in a concentration dependent manner. The inhibitory effects of A. princeps Pamp. extract on tyrosinase were investigated to assess their whitening efficiency. The ethyl acetate fraction demonstrated a 7 times higher tyrosinase inhibitory effect ($IC_{50}=29.20{\mu}g/mL$) than albutin, known as a whitening agent. The antibacterial activity of ethyl acetate fractions against various normal skin flora were measured. The results showed that the antibacterial activity of the fraction was the highest on Staphylococcus aureus, Bacillus subtilis, and Propionibacterium acnes. Antioxidant substances were isolated and purified from the ethyl acetate fractions. Eupatilin and jaceosidin were identified. These results indicate that the extract/fractions of A. princeps Pamp. can function as antioxidant and/or antibacterial agents for the skin.