• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.7 no.2
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• pp.181-195
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• 1997

The purpose of this study was to investigate factors affecting the composition and concentrations of fumes generated from various types of welding processes. The results are as follows. 1. Iron(Fe), zinc(Zn) and manganese(Mn) were predominant in Welding fumes. The Fe content in total fumes was 25.5% in coated electrode and 28.2% in $CO_2$ are welding, and the Zn content was 4.5% and 9.1%, respectively, and the Mn was 3.6% and 7.8%, respectively. 2. It was found that the important factors determining composition and concentration of fumes were type of industries, type of welding processes, type and composition of electrodes, composition of base metals, confinement of workplaces or condition of ventilation, work intensity, coated metals such as lead and Zn in paint. 3. The Mn content in airborne fumes was highly correlated with that of electrode(r=0.77, p<0.01) and was about 4 times higher than that in electrodes or base metals. The results lindicate that Mn is well evaporated into air during welding. The higher vapor pressure of Mn may explain this phenomenon. 4. the airborne total fume concentrations were significantly different among types of industries(p<0.001). The airborne total fume concentration was higher in order of sleel-structure manufacturing($GM=15.1mg/m^3$), shipbuilding($GM=13.2mg/m^3$), automobile-component manufacturing ($GM=7.8mg/m^3$) and automobile assembling industry($GM=3.0mg/m^3$) 5. The airbone total fume concentration was 6 times higher in $CO_2$ welding than in coated electrode welding, and approximately 3 times higher in confined area than in open area, in steel-structure manufacturing industry. 6. The concentration of welding fume outside welding helmet was about 2 times higher than that inside it. It is recommened that air sampling be done inside helmet to evaulate worker's exposure accurately, for it has an outstanding effect on reducing worker exposure to fumes and other contaminants.

• Journal of Periodontal and Implant Science
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• v.31 no.1
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• pp.149-165
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• 2001

This study was performed to define the cytotoxicity and the anti-inflammatory action of Pulsatilla koreana extracts. To analyze cytotoxic effects, gingival and periodontal ligament fibroblasts were used, and anti-inflammatory actions related to reduction of $IL-1{\beta}$ and $PGE_2$ production were performed in vitro, for the suggestion of efficacy and safety on periodontal therapeutic use of Pulsatilla koreana extracts. We extracted ethylacetate and butylalcohol from well-dried and ground Pulsatilla koreana throughout multiple processing, then used different concentration solution(0.1 %, 0.2 %, 0.4 %, 0.01 %, 0.02 %, 0.04 %, 1 %, 2 %) of ethylacetate and butylalcohol extracts to examine eytotoxic effects and anti-inflammatory actions Cytotoxic effects were examined by ELISA reader using MTT(Methyl Thiazol-2-YL-2, 5-diphenyl Tetrazolium bromide)solution following culture of human gingival and periodontal ligament fibroblasts. Synthesis of $IL-1{\beta}$was examined by $IL-1{\beta}$ enzyme-immunoassay(EIA)system after separation and culture of monocyte, and $PGE_2$ was examined by $PGE_2EIA$ system after culture of gingival fibroblasts. The results were as follows: 1. In the MTT test of gingival fibroblasts, the change of optical density was decreased significantly at 2 % of butylalcohol extracts and 0.04 %, 0.1 %, 0.2 %, 0.4 %, 1 %, 2 % of ethylacetate extracts.(p<0.05) 2. In the MTT test of periodontal ligament cells, the change of optical density were not differ significantly. but butylalcohol and ethylacetate extracts except from butylalcohol 0.01 % showed high cell cytotoxity. 3. Both ethylacetate and butylalcohol extracts from Pulsatilla koreana inhibited the synthesis of $IL-1{\beta}$and inhibition effect of ethylacetate extracts were higher than butylalcohol extracts. 4. Both ethylacetate and butylalcohol extracts from Pulsatilla koreana inhibited the synthesis of $PGE_2$, and ethylacetate extracts were higher than butylalcohol extracts. In conclusion, ethylacetate and butylalcohol extracts from Pulsatilla koreana showed little cell cytotoxity for gingival and periodontal ligament fibroblasts, and the inhibition of $IL-1{\beta}$ and $PGE_2$ sysnthesis, therefore it is considered that these extracts can be developed as the therapeutics of the periodontal disease.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.1
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• pp.1-6
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• 2004

$\beta$-Sitosterol is the major phytosterol in higher plants, including fruits and vegetables. The molecule has been shown to have the potential for prevention and therapy for human cancer. We investigated the effects of $\beta$-sitosterol on the cell proliferation of HCT116 human colon cancer cells in order to understand its anti-proliferative mechanism. $\beta$-Sitosterol treatment resulted in the inhibition of cell proliferation in a concentration-dependent manner. The anti-proliferative effect of HCT116 cells by $\beta$-sitosterol was associated with formation of apoptotic bodies and degradation of $\beta$-catenin protein. In addition, $\beta$-sitosterol-treatment induced a marked accumulation of tumor suppressor p53 and a concomitant induction of cyclin-dependent kinase (Cdk) inhibitor p21 without alteration in the levels of cyclins and Cdks. Taken together, these findings provide important new insights into the possible molecular mechanisms of the anti-cancer activity of $\beta$-sitosterol.

• KSBB Journal
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• v.24 no.1
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• pp.75-79
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• 2009

The effect of inorganic, organic nitrogen sources and amino acids on the coenzyme $Q_{10}$ production and coenzyme $Q_{10}$ component ratio was investigated. Among the nine organic nitrogen sources, CSP showed a remarkable enhancing effect on the production of coenzyme $Q_{10}$. But this enhancement was not observed in medium containing Bacto peptone, tryptone, casamino acid and soybean meal. These differences on the production of coenzyme $Q_{10}$ may be due to differences in kinds and amounts of component amino acids and peptides in the various organic nitrogen sources tested. In the addition of inorganic nitrogens, only $(NH_4)_2SO_4$ increase the coenzyme $Q_{10}$ production by 2.0 times compare to the control group. The addition of L-tyrosine to the medium containing Bacto tryptone, was also determined to be crucial for the coenzyme $Q_{10}$ production. But phenylalanin and tryptophan, other aromatic amino acids, had no stimulatory effect on the coenzyme $Q_{10}$ production. These results show that the production and components ratio of coenzyme $Q_{10}$ was greatly affected by the kinds and the concentration of inorganic, organic nitrogen sources as well as amino acids.

• Korean Journal of Construction Engineering and Management
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• v.16 no.1
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• pp.92-100
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• 2015

This study proposes measures to improve management performance of construction projects by re-designing the organizational structures of the Regional Construction Management Administrations of the Ministry of Land, Infrastructure and Transport. The re-designing measures are derived based on the three measures which were established by analyses on status of the Regional Construction Management Administrations, requirements from the current organizational structure, and domestic/overseas examples; the measures are: 1) organizational integration and scope expansion, 2) structural re-organization according to construction projects, and 3) building a knowledge management structure. In order to realize the re-designing measures, sixteen tasks are derived; a milestone is established according to importance, feasibility and lead-lag relationships of these tasks. If these tasks are to be carried out successfully, the management performance of the Regional Construction Management Administrations of the Ministry of Land, Infrastructure and Transport will be expected to improve. Ultimately, the Regional Construction Management Administrations can reduce cost and improve the quality of public service by outsourcing the non-core competence tasks and by concentrating on the construction management for the new infrastructure projects.

• Journal of Oral Medicine and Pain
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• v.32 no.1
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• pp.35-43
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• 2007

This study was conducted to investigate the preventing effects of OPB (water extracts of Rehmannia glutinosa Libosch and Eleutherococcus senticosus Max) on bone loss in ovariectomized rats. Twenty Sprague Dawley rats of 13 week-old were divided into two groups: control group (ovariectomized, OVX)) and experimental group (OVX + OPB). The preventing effects of OPB on bone loss, OPB were fed with 100 mg OPB/kg body weight from 3 days after ovariectomization. The duration of the treatment period was 8 weeks. All bone mineral density, bone mineral content indices and bone strength indices measured by peripheral quantitative computerized tomography (pQCT) and serum bone marker assessment were carried out at end of experiment. pQCT scanning showed that OVX induced a significant decrease in cancellous bone mineral density in the proximal tibia ($-29.8{\pm}3.0%$). These decreases were significantly prevented by the administration of OPB 100 mg/kg ($-21.4{\pm}2.3%$. p<0.05). Bone strength indices showed significant difference between OVX and OPB treated rats (anti-fracture, anti-twisting, p<0.05). These data suggested that administration of OPB inhibited the loss of bone in OVX rats. CTx level were lower than in the OPB-treated animals compared with OVX. However there was no significant difference between OVX and OPB treated OVX rat. Our results suggest that OPB is effective in preventing the development of bone loss induced by ovariectomy in rats.

• Journal of Periodontal and Implant Science
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• v.25 no.3
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• pp.694-702
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• 1995

Using the Korean red ginseng saponin, which is known to world-wide and thd effects of it have been investigated by many reserachers for years. Ginseng saponin, one of the major components of Korea ginseng root, has many various biologic effects, such as cytotoxic effect, tumorcidal activity, protein biosynthesis and membrane modifying effect. The purpose of this study was to evaluate effects of ginseng saponin on the alkaline phosphatase activity of ROS cells in culture. After ROS cells were seeded into a 96-well plate, 96-well plate cultured until confluence was obtained. To evaluate cytotoxic effect of total saponin in cultured ROS cells, the plates were added to each total saponin concentration (0-1mg/ml). After 48hr., cells were counted by stain with 0.2% trypan blue at randomly selected field microscopically. Also, to evaluate alkaline phosphatase(ALP) activity of total saponin in cultured ROS cell, the plate was added to each total saponin concentration (0-1mg/ml) and ALP activity was assayed. To evaluate time-course of ALP activity, $31.25{\mu}g/ml$ of saponin added to 96-well plate. After culture of 6, 12, 24 and 48hr., ALP activity test was performed. To evaluate effect of cycloheximide in ALP activity, 96-well plate was added to saponin and cycloheximide. In control group, the plate was added saponin only. The results were as follows. 1. After the various concentration of total saponin was added in the medium, 500 and $1000{\mu}g/ml$ of total saponin showed cytotoxic effect of ROS(P<0.005). 2. In contrast to control group, 7.6, 15.6, 31.25, 62.5 and $250{\mu}g/ml$ of total saponin increased ALP activity significantly. 3. Otherwise, 500 and $1000{\mu}g/ml$ of total saponin decreased ALP activity significantly(P<0.005). 4. As the time span increases, $31.25{\mu}g/ml$ of total saponin increased ALP activity. 5. Cycloheximide decreased saponin-indueced ALP actitity in ROS(P<0.005). These results suggest that Ginseng total saponin stimulates the ALP activity of rat osteoblastic cells.

• Journal of Bio-Environment Control
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• v.16 no.1
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• pp.62-66
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• 2007

This study was carried out to develop the stable plug seedling production for hydroponics of spinaches by various nursery media, plug tray size and seed number per plug tray cell. When plant grown in various nursery media, the seeding stand rate was shown in order of granular rockwool with good water retention, granular rockwool>granular rockwool mixed with pearlite>cocopeat>pearlite>poly urethane foame. Thus, poly urethane foame indicated the lower seedling stand rate. There was no difference in growth of the seedlings md the seeding stand rate by the plug tray size, and no significant difference in the plant height and the number of leaves among the seed number per plug tray cell. But, leaf area of plant in 2 grains seeding per cell was $113.0cm^2$, was wider in compared with 5 grains seeding of which leaf area was $88.0cm^2$. Accordingly, the leaf area per plant decreased as more and more the number of seeds per plug tray cell increased. The fresh weight of a plant per plug tray cell was the heaviest with 12.5g in the 2 grains, and the total fresh weight of plants per cell was 33.9g in 4 grains seeding, thus it tended to was bigger compared with other treatments. Consequently, given that the number of seeds per cell was decreased, the fresh weight of a plant increased. On the other hand, the total fresh weight per cell showed a tendency to be reducing as more and more the number of seeds per plug tray cell decreased. The yield in the 4 grains seeding was increased by 46% as $14,910kg{\cdot}ha^{-1}$ in compared with the yield in 2 grains seeding as $10,200kg{\cdot}ha^{-1}$.

• Journal of Mushroom
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• v.5 no.2
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• pp.51-58
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• 2007

These experiment was conducted to find the superior strain selection, cultivation technique and optimum environmental condition of nameko mushroom culture using plastic container. The results was following as Mycelium of Pholiota nameko grown well at MCM and Hamada media, and its media acidity was pH 6~7. The optimum temperature condition for growing mycelium was $25^{\circ}C$. Under $15^{\circ}C$ and above $30^{\circ}C$ of temperature condition, mycelium growing speed was delayed remarkably. Among the 29 strains of nameko mushroom, the most productive strains was JNM19007, JNM19026, JNM19027 and JNM19028. The optimum media composition rate for produce fruitbody was pine sawdust 80% + wheat bran 20%. In this condition, the average fruitbody amount was 188g per 1,100cc container. The optimum post-culturing period was 50 days and mushroom sprout appeared 7 days after old mycelia removed. The suitable temperature was $12^{\circ}C$ for induce sprout, growing period was $16^{\circ}C$ and the optimum relative humidity was 95% in all culturing periods.

• Asian Journal of Turfgrass Science
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• v.25 no.2
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• pp.160-170
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• 2011

Commercial formulation of fungicides was studied in vitro for sensitivity against Typhula species causal agents of Typhula blight. Efficacies of fungicides application, spray volume, nozzle types and fungicides applied time (early fall and late fall) were evaluated for their influence on the chemical control of Typhula blight of turfgrass during the winter season in Wisconsin. All fungicides effectively reduced the mycelial growth of eight isolates of Typhula spp. in vitro on potato dextrose agar (PDA) media. For inhibitory effects on mycelial growth of eight isolates, propiconazole was the most effective at $1.0{\mu}g$ active ingredient (a.i) / ml of PDA. Typhula incarnata two isolates were significantly more sensitive to all fungicides of PDA than six isolates of three varieties of T. ishikariensis. For 2 years in field experiment, unsprayed control has significantly more disease severity than seven fungicides were applied to field plots at two locations. Propiconazole was the most effective for controlling Typhula blight, at two locations in both years. The level of disease control was not dependent on fungicides spray volume or nozzle types at two locations. The disease damage treated with triadimefon applied time (early fall and late fall) was not significantly different at two location for two years.