• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.31 no.4
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• pp.291-299
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• 2005

Objectives : It is well known that cigarette smoking is harzardous to the osseointegration of dental implant, due to the impaired wound healing accompanied by reduced alveolar bone density. The aim of this study is to evaluate the influence of cigarette smoke on the implant osseointegration by the time factor consideration. Materials and methods : Twenty-four male Spraque-Dawley rats (8 weeks, weighting 200 to 250g) were used in this study. In the experimental group, 13 rats were exposed to cigarette smoke, 8 minutes per day during 6 weeks, and 12 rats in the control group were not exposed at any time. RBM (Resorbed blasting media) surfaced implant (diameter 3.3mm, length 5.0mm, AVANA Co., Korea) was placed in the right femur of each rat. Each implant with surrounding bone was prepared with microtome (cutting band 0.2mm$^{(R)}$, EXAKT Co., Germany) after 1 day, 2, 4, 8 and 12 weeks and stained with toluidine blue (1%). Another clinical investigation of each implant was also done at each evaluation time. Results : Clinical investigation around implant fixture showed that there were no significant differences between the control and experimental group. Microscopic observation around implant fixture showed that there were significant differences between the control and experimental group at the initial stage after implant fixture installation. Experimental group showed a decreased bone to implant contact within 4 weeks compared to control group, but showed similar characteristics after 4 weeks. Conclusion : Smoking inhalation effect on the dental implant showed the impaired wound healing by vasoconstriction and decreased intramedullary blood flow at initial stage of osseointegration. This experimental results can be clinically useful to the implant surgery of smoking patients.

• Korean Journal of Environment and Ecology
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• v.31 no.2
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• pp.174-187
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• 2017

For the purpose of evaluating the restoration effect of vegetation, in this study, the areas where vegetation was restored had been monitored for 6 years, from 2008 to 2013. The areas were restored through some techniques by utilizing forest resources and nearby forest resources: biotope restoration method, forest topsoil paving method and small diameter trees planting method. Biotope restoration method is indicated the most similar properties to the existing natural forest just after they were restored because the forest likely to be deteriorated was transplanted. Forest topsoil paving method is expected that long-time will be taken for plants to grow to form the tree layer. However, the method is expected to acquire high restore the places of empty lands such as cutting areas. Community planting method is coverage can be increased for short time, relying on the sizes of planted trees, and the tree layer can be formed. Consequently, this method is expected to create high effect if the sizes of trees are considered after the right judgement of candidate site for restoration. This study is meaningful in that each type of restoration is monitored to observe the change of triggered by the succession process to forest. The study results can play as the reference data which can be utilized and applied to the area requiring vegetation restoration or to the area facing the damage of forest resources.

• The Journal of Korean Academy of Prosthodontics
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• v.41 no.3
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• pp.319-324
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• 2003

Statement of problem. Adhesives in dentistry playa major role in the success of restorative treatments. In the treatment of all ceramic restoration it is needed to find the adequate bond strength between enamel and dentin. Purpose. The purpose of this study was to evaluate shear bond strength of resin cement bonded to extracted human uncut enamel, cut enamel, and dentin in vitro. Material and methods. Ten freshly extracted anterior teeth without any previous restorative treatments were chosen. The extracted teeth were embedded in PMMA cold acrylic in the shape of a cylinder, 25 mm in diameter by 25 mm in height. The bonding system used was as follow: Uni-Etch (32% phosphoric acid), One-Step adhesive, Duolink resin cement. The specimens were acid etched and rinsed with water. Two layers of One-Step adhesive were coated with a disposable brush on the uncut enamel. VIP curing light at $500mV/cm^2$ was used to cure the adhesive. For cut enamel shear bond test, the specimen used for uncut enamel was further reduced approximately $0.3{\sim}0.5mm$ using a laminate preparation diamond bur (0.3 mm in depth). The specimens were subsequently treated with 320-grit SiC paper followed by 600-grit SiC paper and cleaned with distilled water. The bonding procedure on the cut enamel was same as uncut enamel bonding procedure. For dentin bonding test, the specimen used for cut enamel was further reduced approximately $0.5mm{\sim}1.0mm$ using a laminate preparation diamond bur (0.5 mm in depth of diamond cutting). The amount of reduction was evaluated with the silicone mold. The specimens were subsequently treated with 320-grit SiC paper followed by 600-grit silicon carbon paper and cleaned in distilled water. The bonding procedure on the dentin was same as uncut enamel bonding procedure. All samples were mounted and secured on the Ultradent shear bond test sample holder, and Ultradent restricted shear bond testing device was used with Universal Instron machine until fracture. Analysis of variance (ANOVA) test was performed comparing the result at P<0.05. Multiple comparison (Tukey) was used to compare each groups. Result. The result showed that the mean value in shear bond strength of resin cement bonded to uncut enamel, cut enamel and dentin were 27.04 Mpa, 30.25 Mpa and 26.39 Mpa with respect. Conclusion. Within the limitation of this study, the mean value of the shear bond strength of cut enamel was higher than those of uncut enamel or dentin. However there existed no statistical differences between three different human dentition substrates due to increased adhesive characteristics.

• Analytical Science and Technology
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• v.17 no.4
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• pp.355-362
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• 2004

Fission products and Inter reaction layer of $U_3Si-Al$ dispersion fuel, irradiated in HANARO research reactor with 121 kW/m of maximum liner power and 63 at% of average burn-up, was characterization by EPMA (Electron Probe Micro Analyzer). The fuel punching system developed by Irradiated Materials Examination Facility (IMEF) has used to make these samples for the EPMA. With this system a very small and thin specimen which is 1.57 mm in diameter and 2 mm in thickness respectively has been fabricated to protect the EPMA operator from high radioactive fuel and to mini-mize the equivalent dose rate less than 150 mSv/h. EPMA was performed to observe layers of sectional, Inter-reaction and oxide with specimens of cutting and polished. Stoichiometry in the Inter-reaction layer with $16{\mu}m$ of thickness was $U_{2.84}$ Si $Al_{14}$ with calibration of $UO_2$ and $U_{3.24}$ Si $Al_{14.1}$ with calibration of standard specimen. metallic precipitates in this layer were not observed using fission products examination.

• Restorative Dentistry and Endodontics
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• v.21 no.2
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• pp.451-469
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• 1996

The purpose of this study was to investigate the effect of calcium hydroxide and glass ionomer cement fillings on the levels of $LTB_4$ and $LTC_4$ in experimentally inflamed rat dental pulp. The dental pulp in the mandibular incisor of wistar rat was irritated by cutting a 5mm deep hole in the dentin with a twist drill bur of 0.5mm diameter, without cooling. The cavities were filled with calcium hydroxide(light-cured) and glass ionomer cement(light cured). The untreated pulp served as control tissue specimen. After cavity preparations, the rat with or without various treatment were sacrificed in various time by decapitation. The dental pulp tissue were carefully removed and the concentrations of $LTB_4$ and $LTC_4$ were determined by radioimmunoassay. And pulps were examined histologically to observe inflammatory feature. The result were obtained as follows : 1. The inflammatory features of pulps were observed microscopically in all experimental groups. And degree of inflammation was decreased with time. 2. The concentrations of $LTB_4$ and $LTC_4$ for all experimental groups were significantly higher than those for control group 6 hours after cavity preparation(p<0.05). 3. The group filled with calcium hydroxide was the lowest, and the group filled with glass ionomer cement, the group of irritation in that order showed increased concentrations of $LTB_4$ and $LTC_4$ 6 hours after cavity preparation. In the concentrations of $LTB_4$, significant differences among 3 groups were noted(p<0.05). 4. The group filled with calcium hydroxide was the lowest, and the group filled with glass ionomer cement, the group of irritation in that order showed increased concentrations of $LTB_4$ and $LTC_4$ 24 hours after cavity preparation. And there were statistically significant difference in concentrations of $LTB_4$ between the group of irritation and the group filled with calcium hydroxide(p<0.05). 5. The group filled with calcium hydroxide was the lowest, and the group filled with glass ionomer cement, the group of irritation in that order showed increased concentrations of $LTB_4$ and $LTC_4$ 48 hours after cavity preparation. But no statistically difference was found (p>0.05). 6. The concentrations of $LTB_4$ and $LTC_4$ in all experimental groups were highest level at 6 hour after experiment and decreased as time progresses(correlation coefficient>0.8).

• Journal of Korean Society of Forest Science
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• v.20 no.1
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• pp.45-50
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• 1973

This study was investigated the methods of vegetative propagation for new Lespedeza varieties. Experimental matterials were used 6 Lespedeza species; L. maximowiczii, L. cyrtobotrya, L. angustifolioides, L. bicolor, L. maximowiczii var. tomentella, and L. japonica var. intermedia. In April a year branches were cut 15-20cm length and 3-4mm thickness and planted in sand bed (depth 150cm) to be sterilized by the 0.1% solution of Uspulun. And then the cutting beds were irrigated and shaded. The results are as follows. 1. The rooting rates of the cuttings could be found so variable among varieties from 69% of L. maximowiczii var. tomentella to 50.3% of L. japonica var. intermedia. 2. The growth performance showed statistically significant difference at 1% level among varieties. L. maximowiczii was the best, while L. japonica var. intermedia showed the wrost growth performance of them. 3. The average number of roots with more than 5 cm length per stock was revealed statistically significant difference at the 1% level among varieties from the greatest number of 6.4 of L. maximowiczii var. tomentella to the smallest number of 2.3 of L. japonica var. intermedia. 4. Total average length of the roots per stock was statistically significant so different at 1% level from the longest 279.8cm of L. maximowiczii var. tomentella to the shortest 41.1cm of L. japonica var. intermedia. 5. The average ndules with more than 1 mm in diameter per stock was statistically significant so different at 1% level among varieties from the greatest number of 34.4 of L. maximowcizii to the smallest numqer of 4.6 of L. japonica var. intermedia.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.552-555
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• 2009

A new standard rose cultivar "Snow Day" was bred from the cross between pink standard cultivar "Saphia" and pink standard cultivar "Bridal Beauty" at the National Institute of Horticulture & Herbal Science. The cross was made in 2003 and "Snow Day" was finally selected in 2008 after evaluating characteristics for three years from 2006 to 2008. A white standard cultivar, "Snow Day" grows vigorously and resistant to powder mildew. The major characteristics of this cultivar are $152stems/m^2/year$ in yield, 81.8 cm in length of cut flower, 11.3 cm in flower diameter, 29.2 in petal number, and 13.7 days in vase life. This cultivar can be propagated by both cutting and grafting. The consumer's preference for this cultivar is relatively higher than that for the control cultivar, "Tineke".

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.616-619
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• 2009

A new standard rose cultivar "Red Charm" was bred from the cross between deep red standard cultivar "First Red" and light red standard cultivar "Cardinal" at the Jeollanamdo Agricultural Research and Extention Services (JARES). The cross was made in 2003 and, "Red Charm" was finally selected in 2008 after investigating characteristics for three times from 2007 to 2008. "Red Charm", a red standard cultivar has good flower shape and velvet flower color. The major characteristics of this cultivar are on average $119.3stems/m^2/year$ in yield, 69.5 cm in length of cut flower, 10.3 cm in flower diameter, 36.9 in petal number, and 9.8 days in vase life. This cultivar can be propagated by both cutting and grafting. The consumer's preference of this cultivar, "Red Charm" is relatively higher than that of control cultivar, "Red Velvet".

• Korean Journal of Breeding Science
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• v.43 no.6
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• pp.528-531
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• 2011

A new spray rose cultivar 'Cherry Tea' was bred from a cross between pink spray cultivar 'Pinocchio' and yellow spray cultivar 'Flair' at the National Institute of Horticultural Research Institute. The cross was made in 2003 and 'Cherry Tea' was finally selected in 2008 after evaluating characteristics for three years from 2006 to 2008. 'Cherry Tea', a light orange spray cultivar grows vigorously and has good vase life. The major characteristics of this cultivar are $137stems/m^2/year$ in yield, 68.8 cm in length of cut flower, 5.5 cm in flower diameter, 34.0 in petal number, and 12.4 days in vase life. This cultivar can be propagated by both cutting and grafting. The consumer's preference of this cultivar is relatively higher than that of control cultivar, 'Little Marble'.

• FLOWER RESEARCH JOURNAL
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• v.18 no.1
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• pp.50-56
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• 2010

This experiment was carried out to examine the effect of a silicate fertilizer on the growth and development of potted plants. Cutting of Kalanchoe blossfeldiana 'Kaluna' and 'Taos', and Dianthus caryophyllus L. 'Kazan' and 'Tula' were grown in 50 and 128-cell plug trays, respectively. Rooted cuttings transplanted to the mixture of a commercial medium and perlite (5:1, v/v) supplemented with a silicate fertilizer at 0, 40, 80, 120 or $160g{\cdot}L^{-1}$ medium was evaluated. A silicate fertilizer supplementation at $40g{\cdot}L^{-1}$ medium resulted in the greatest plant height, leaf thickness, and root fresh and dry weights in both kalanchoe and carnation. However, plant height was suppressed in the treatment of a silicate fertilizer supplementation at higher concentrations in both kalanchoe and carnation. According to the scanning electron microscope images of transversal sections of tissues of roots and leaves in kalanchoe and carnation, the treatment of a silicate fertilizer supplementation at $40g{\cdot}L^{-1}$ medium resulted in plants with more compact tissue than the control.