• Restorative Dentistry and Endodontics
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• v.45 no.3
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• pp.34.1-34.7
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• 2020

Objectives: This study evaluated by using micro-computed tomography (micro-CT) the filling ability and sealer apical extrusion promoted by a new Sealer Injection System (SIS; Angelus) with side openings needle, in comparison with the conventional injection system, associated with a new ready-to-use calcium silicate-based sealer (Bio-C Sealer). Materials and Methods: Acrylic resin models containing a main curved artificial canal and 3 simulated lateral canals in apical, middle and cervical thirds were used. The main root canals were prepared using a rotary system up to size 35.05. The canals were filled with Bio-C sealer by using a single cone technique and the conventional delivery system or SIS. Samples were scanned in micro-CT. The percentage of voids throughout the entire extension of the main root canal and in each third of the lateral canals, besides the apical extrusion of the sealer was calculated. Data were submitted to t-test (p < 0.05). Results: There was no difference between both systems in the main root canals filling. Although the volume percentage of voids was similar in the apical and middle thirds of lateral canals, SIS had the greatest filling ability of the cervical third lateral canal. Moreover, the conventional system showed the highest apical extrusion of the sealer. Conclusions: The conventional and SIS obturation systems had an appropriate filling ability of the main root canal. SIS had the best filling of the cervical third of the lateral canals, besides lower sealer apical extrusion, suggesting its clinical indication.

• Journal of Korean Society of Forest Science
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• v.101 no.2
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• pp.317-323
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• 2012

This study was performed in order to explore the growth characteristics by growing stage in the containerized seedling and the bare root seedling of Chamaecyparis obtusa Sieb. et Zucc., which is the major plantation species of Korean southland. The height growth of 1-year-old bare root seedlings was better than containerized seedlings, which grew in the containers with capacity of 31.2 mL and 300 mL. The root collar diameter growth was the best in the containerized seedlings of container with 300 mL. The 2-year-old bare root seedlings were surveyed to be better in the height and root collar diameter growth than the containerized seedlings of container with 300 mL. In the comparison of dry mass production, it was the highest in 32 mL containerized seedlings as for 1-year-old above ground and in 300 mL containerized seedlings as for below-ground and total dry mass production. In case of 2-year-old seedlings, it was indicated to be high in bare root seedling as for the part above ground and in dry mass production of the containerized seedling as for the part below ground. In the comparison on root morphological traits of seedlings such as the total root length, the root project area, the root surface area, the average diameter in root, and the root volume, all of 1 and 2-year -old containerized seedlings showed the higher growth than the bare root seedlings except the average diameter in root. Synthesizing the results of this experiment, the containerized seedlings are relatively excellent in root development compared to bare root seedlings in the process of producing seedlings of C. obtusa, thereby being judged to have grown into excellent seedlings.

• The Korea Journal of Herbology
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• v.29 no.6
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• pp.85-93
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• 2014

Objectives : We compared with the effects of different parts (root head, root body and hairy root) of Angelica gigas Nakai (Angelicae Gigantis Radix, AG) with on middle cerebral artery occlusion(MCAO)-induced ischemic rats, and on LPS-induced inflammatory response in BV2 microglia. Methods : The 30% ethanol and water extracts of different parts of AG were prepared. Each extract (50 and 100 mg/kg) was administrated intraperitoneally once in MCAO-induced ischemic rats. We measured infarction volumes by TTC staining, and investigated the expression of iNOS, Bax, Bcl-2 and caspase-3 by Western blot. BV2 cells were treated with each extract for 30 min, and then stimulated with LPS. The levels of NO was measured by Griess assay. The expression of iNOS, Cox-2 and proinflammatory cytokines ($TNF-{\alpha}$, $IL-1{\beta}$, and IL-6) were determined RT-PCR and Western blot. The phosphorylation of ERK1/2 and JNK MAPK was determined by Western blot. Results : Among different parts of AG, the 30% ethanol and water extracts of hairy root significantly decreased infarction volume in ischemic brains and inhibited the expression of iNOS, bax and caspase-3. The extracts of hairy root significantly inhibited LPS-induced production of NO, $TNF-{\alpha}$ and IL-6 in BV2 cells, and suppressed the expression of iNOS and COX-2. The hairy root extracts attenuated LPS-induced phosphorylation of ERK1/2 and JNK MAPK in BV2 cells. Conclusions : Our results indicate that the root hairy of AG has a good neuroprotective and anti-inflammatory effects in ischemic stroke compared to other parts.

• Journal of Microbiology and Biotechnology
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• v.29 no.11
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• pp.1777-1789
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• 2019

Drought is more concerned to be a huge problem for agriculture as it affects plant growth and yield. Endophytic bacteria act as plant growth promoting bacteria that have roles for improving plant growth under stress conditions. The properties of four strains of endophytic bacteria were determined under water deficit medium with 20% polyethylene glycol. Bacillus aquimaris strain 3.13 showed high 1-aminocyclopropane-1-carboxylate (ACC) deaminase production; Micrococcus luteus strain 4.43 produced indole acetic acid (IAA). Exopolysaccharide production was high in Bacillus methylotrophicus strain 5.18 while Bacillus sp. strain 5.2 did not show major properties for drought response. Inoculation of endophytic bacteria into plants, strain 3.13 and 4.43 increased height, shoot and root weight, root length, root diameter, root volume, root area and root surface of Jerusalem artichoke grown under water limitation, clearly shown in water supply at 1/3 of available water. These increases were caused by bacteria ACC deaminase and IAA production; moreover, strain 4.43 boosted leaf area and chlorophyll levels, leading to increased photosynthesis under drought at 60 days of planting. The harvest index was high in the treatment with strain 4.43 and 3.13 under 1/3 of available water, promoting tuber numbers and tuber weight. Inulin content was unchanged in the control between well-watered and drought conditions. In comparison, inulin levels were higher in the endophytic bacteria treatment under both conditions, although yields dipped under drought. Thus, the endophytic bacteria promoted in plant growth and yield under drought; they had outstanding function in the enhancement of inulin content under well-watered condition.

• Journal of Bio-Environment Control
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• v.32 no.3
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• pp.205-209
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• 2023

Mechanical stimulation induce the morphological changes in plants. In this study, we investigated the growth changes of tomato seedlings applicated to mechanical stimulation. The brushing treatment was used for mechanical stimulation. The brushing treatment interval was 2 hr using transfer device attached acrylic film from 10 days after sowing. Growth parameter of tomato seedlings were measured 3-day intervals to investigate the growth changes during brushing treatment. The plant height and leaf area were decreased in brushing treatment than the control, and the fresh and dry weights of shoot didn't have significant difference in the control and brushing treatment. The total root length and root surface area were increased in brushing treatment compared than the control, and root volume has no significant difference in the control and brushing treatment. In conclusion, these results suggest that the application of brushing treatment on tomato seedling make shorten plant height and well-development root morphological characteristics.

• Communications for Statistical Applications and Methods
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• v.17 no.5
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• pp.713-724
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• 2010

Calculating or estimating the proper insurance premium is very important decision making process for both the policyholder and the insurance company. The credibility theory is one of the most important theories in actuarial science to get the proper premium. In this research, we introduce the rule of relative exposure volume, the square root rule and the B$\ddot{u}$hlmann credibility, and estimate the new premiums based on these methods. By real data analysis, the accuracy of these credibility methods are compared.

• Restorative Dentistry and Endodontics
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• v.19 no.1
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• pp.97-105
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• 1994

The purpose of this study was to evaluate the smear layer removing efficiency of two root canal preparation techniques. Twelve single-rooted teeth were used in two groups of six each. Group 1 was biomechanically prepared by hand using a K-file with a high volume of normal saline irrigation. Group 2 was. prepared by using ultrasonically activated K-file with a constant high volume of normal saline irrigation. After the experimental procedures, each root was split saggitally. The removing efficiency of the preparation methods were assessed in terms of surface condition of the canal walls at three levels, those coronal, middle, and apical thirds. On the basis of remaining debris, presence of smear layer, and patency of dentinal tubules, each canal was evaluated according to a scale form 0 to 2. A statistical analysis was used to indicated any significant differences in surface condition between the two methods. There was no statistical significance between hand instrumentation and ultrasonic instrumentation at the cervical third but removing efficiency of ultrasonic instrumentation was superior. No statistically significant differences were obhserved for middle or apical third.

• Journal of Korean Society of Forest Science
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• v.103 no.4
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• pp.556-563
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• 2014

The purpose of this study was to evaluate the effects of container types on seedling growth of Chamaecyparis obtusa (2-year-old) in the container nursery culture. We used three container types [20 cavities (400 mL/cavity, $150seedlings/m^2$), 24 cavities (320 mL/cavity, $200seedlings/m^2$), and 35 cavities (240 mL/cavity, $260seedlings/m^2$)] and measured root collar diameter (RCD), height, biomass, root density and seedling quality index (SQI). The RCD, height, biomass, root density and SQI were the highest at 20 cavities/tray because this container has the largest volume and lowest seedling density. However, H/D and T/R ratio at all container types were not significantly different. The total biomass per unit area ($m^2$) were the lowest at 35 cavities/tray and those at both 20 and 24 cavities/tray were not significantly different. Container volume was positively correlated with RCD, height, biomass, root density and SQI except for H/D and T/R ratio, while seedling density negatively affected on them. Based on these results, 20 cavities/tray are optimal for container seedling production of C. obtusa. Usage of optimal container will make us get better quality seedlings and reduction of production costs in the container nursery as well as good field performances with higher survival rate in plantation.

• Journal of Korean Society of Forest Science
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• v.101 no.2
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• pp.324-332
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• 2012

The purpose of this study was to evaluate the effects of container types on seedling growth of Betula costata, Liriodendron tulipifera, Fraxinus rhynchophylla, Fraxinus mandshurica, Zelkova serrata, and Ulmus parvifolia in the container nursery system. We used three container types [20 cavities (150 seedlings/$m^2$-400 mL), 24 cavities (200 seedlings/$m^2$-320 mL), and 35 cavities (260 seedlings/$m^2$-240 mL)] and measured root collar diameter (RCD), height, biomass, seedling quality index (SQI), and root density. The root collar diameter, height, biomass, SQI, and root density of seedlings were the highest at 20 cavities/tray in all six species because this container type has the largest volume and lowest seedling density. However, F. rhynchophylla growth at both 20 and 24 cavities/tray, Z. serrata growth at both 24 and 35 cavities/tray and B. costata growth at all sizes were not significantly different. As expected, container volume was positively correlated with RCD, height, and biomass of five species except for Z. serrata, but seedling density negatively did. Based on these results, 20 cavities/tray are optimal for L. tulipifera, F. mandshurica, and U. parvifolia, 20 or 24 cavities/tray for F. rhynchophylla, 24 or 35 cavities/tray for Z. serrata, and 35 cavities/tray for B. costata, respectively. Usage of optimal container will make us get good quality seedlings as well as reduction of production costs in the container nursery.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2004.04a
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• pp.18-21
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• 2004

A GFRP based composite blade was developed for a 750kW wind energy conversion system of type class I. The blade sectional geometry was designed to have a general shell-spar structure. The load cases specified in the IEC61400-1 international specification were considered. For withstanding all relevant extreme loads, the structural analysis for the complete blade was performed using a commercial FEM code. The static load carrying capacity, buckling stability, blade tip deflection and natural frequencies at various rotational speeds were evaluated to satisfy the strength requirements in accordance with the IEC61400-1 and GL Regulations. For designing a lightweight blade, the thickness and the lay-up pattern of the skin-foam sandwich structures were optimized iteratively using the DOT program T-bolts were used for joining the blade root and the hub, which were modeled using a 3D FE volume model. In order to confirm the safety of the root connection, the static stresses of the thick root laminate and the steel. bolts were predicted by taking account of the bolt pretension and the root bending moments. The calculated stresses were compared with the material strengths.