• Restorative Dentistry and Endodontics
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• v.35 no.3
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• pp.164-172
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• 2010

During a composite resin restoration, an anticipating contraction gap is usually tried to seal with low-viscosity resin after successive polishing, etching, rinsing and drying steps, which as a whole is called rebonding procedure. However, the gap might already have been filled with water or debris before applying the sealing resin. We hypothesized that microleakage would decrease if the rebonding agent was applied before the polishing step, i.e., immediately after curing composite resin. On the buccal and lingual surfaces of 35 extracted human molar teeth, class V cavities were prepared with the occlusal margin in enamel and the gingival margin in dentin. They were restored with a hybrid composite resin Z250 (3M ESPE, USA) using an adhesive AdperTM Single Bond 2 (3M ESPE). As rebonding agents, BisCover LV (Bisco, USA), ScotchBond Multi-Purpose adhesive (3M ESPE) and an experimental adhesive were applied on the restoration margins before polishing step or after successive polishing and etching steps. The infiltration depth of 2% methylene blue into the margin was measured using an optical stereomicroscope. The correlation between viscosity of rebonding agents and mciroleakage was also evaluated. There were no statistically significant differences in the microleakage within the rebonding procedures, within the rebonding agents, and within the margins. However, when the restorations were not rebonded, the microleakage at gingival margin was significantly higher than those groups rebonded with 3 agents (p < 0.05). The difference was not observed at the occlusal margin. No significant correlation was found between viscosity of rebonding agents and microleakage, except very weak correlation in case of rebonding after polishing and etching at gingival margin.

• The Korean Journal of Emergency Medical Services
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• v.23 no.3
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• pp.97-110
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• 2019

Purpose: This study aimed to investigate the role of life stress in the relation between health behaviors and bioethics awareness among paramedic students. Methods: This study recruited 238 paramedic students in F and R areas as participants. Multiple regression analysis was performed using Baron and Kenny's three-step procedure. Results: In the first stage, health behaviors had a significant effect on life stress (β=-.202, p<.01). In the second stage, health behaviors had a significant effect on bioethics awareness (β=.240, p<.001). In the third stage, life stress had a significant influence on bioethics awareness (β=-.167, p<.01). In the fourth stage, the regression coefficient of the third stage (β=.137) was less than that of the second stage (β=.159). In addition, when controlling for life stress, health behavior was shown to affect bioethics awareness (β=.206, p<.01). The mediating effect of life stress was found to be significant in the relation between health behavior and bioethics awareness (Z=2.04, p<.05). Conclusion: As health behavior is a factor that affects bioethics awareness through the mediation of living stress, universities should prepare training programs to improve the health behavior and reduce the life stress among students.

• Journal of Korean Society of Forest Science
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• v.61 no.1
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• pp.15-19
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• 1983

To establish the stand volume table of Pinus koraiensis S. et Z. and Larix leptolepsis Gord. mean diameter at breast height (D), mean height, basal area per ha, stand from height (H.F), basal area height, number of trees per ha, volume per ha, stand age and site were investigated for 107 plots of P. koraiensis and 82 plots of L. leptolepsis throughout the country. The obtained results are as follows; 1) the relationships between stand volume (V) and H.F. were log V=1.3855+0.1168 H.F and log V+0.9929+0.1543 H.F in P. koraiensis and L. leptolepsis, respectively. 2) The relationship between D and H.F was estimated as H.F = 1.2569+0.2576D for P. koraiensis and as H.F = 4.3045+0.1443D for L. leptolepsis 3) Estimated errors calculated with the application of these stand volume tables were 18.29% and 19.22%r for P. koraiensis and L. leptolepsis respectively.

• Journal of Korean Society of Forest Science
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• v.75 no.1
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• pp.19-24
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• 1986

Present studies were carried out to understand the way of propagation of Osmanthus which has much value as ornamental trees in southern parts of Korea. The results of these experiments were summarized as follows: 1. In order to increase the survival of Osmanthus, scions of Osmanthus was grafted on the stocks of Ligustrum obtusifolium S. et Z. The survival of the grafts were 63% for Osmanthus fragrans var. aurantiacus Makino and 60% for Osmanthus asiaticus Nakai. 2. The growth of the grafts was initiated from 28th day after the grafting and the height growth resumed three times, and the growth percentage was 63% for Osmanthus fragrans var. aurantiacus and 59% for Osmanthus asiaticus. 3. Cutting medium mixed with perlite and vermiculite (1:1) gave better results than either use of them separately, and the rooting percentage was 93% for Osmanthus fragrans var. aurantiacus and 90% for Osmanthus asiaticus. 4. Rooting percentage of cuttings was lower in hard-wood cutting than that of in green-wood cutting. 5. Grafts showed fairly good height growth in July and September, and ceased growth in October. 6. Correlation between height growth and diameter of root collar of grafts in case of Osmanthus fiagrans var. aurantiacus was highly significant and showed linear correlation ($r=0.70^{**}$)

• Korean journal of applied entomology
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• v.25 no.2 s.67
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• pp.85-92
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• 1986

This study was conducted to investigate host plant, bionomics, and damage on Bamboo Leaf Rollers in Chonnam area. Species of the leaf rollers attacking the bamboo trees in Chonnam area were Microstega jessica (Butler) and Sinibotys evenoralis (Walker). Among these species, M. jessica (B.) and S. evenoralis (W.) were observed in Damyang but S. evenoralis (W.) alone was found in Naju and Hwasoon. Among the 4 host plant species observed, Phyllostachys nigra var. henonis S., and P. nigra M. were first recorded as host plants of M. jessica (B.), and P. nigra var. henonis (S.) as host plant of S. evenoralis (W.). The occurrence of the M. jessica (B). was once a year with the peak about late May, whereas the occurrence of S. evenoralis (W.) was 2 times a year and the peaks were early June and mid-July, respectively. The average periods of each stage of M. jessica (B.) were 8 days for egg, 293 days for larva, 16 days for pupa, and the longevity of the adult was 12 days for females and 9 days for males. The average periods of each stage of S. evenoralis (W.) were in 1st generation, 11 days for egg, 28 days for larva, 12 days for pupa, and the longevity of the adults was 18 days for females and 15 days for males; and 2nd generation was 7 days for egg, 261 days for larva, 20 days for pupa, and the longevity of the adults was 11 days for females and 10 days for males. The time of most adult emergence of M. jessica (B.) was from 6 p.m. to 4 a.m. and the peak was 8 p.m. to 10 p.m. M. jessica (B,) overwintered as 6th instals in Bamboo shoot sheath but S. evenoralis (W.) overwintered as $1st{\sim}2nd$ instals on the tree leaves of Bamboo. The percentage of damaged leaves with different heights of Bamboo trees were 67.1% at upper portion, 19.0% at middle portion, 14.0% at lower portion. The percentage of damaged loaves with different Bamboo species was 57.0% on P. nigra var. henonis S., 36.5% on P. bambusoides S. et Z., 14.5% on P. pubescens M.. It was showed highly significant negative correlation between percentage of damaged bamboo leaves an tree growth stages.($r=-0.739^{**}$)

• Korean Journal of Environmental Biology
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• v.27 no.2
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• pp.183-190
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• 2009

Characterization of the analysis of forest vegetation, soil environmental conditions and water quality were performed from March 2003 to March 2007. The two basins were characterized by cultivated area (Kaesim reservoir) and mountain area (Jangchan reservoir), and divided into eleven small basins, where dynamics of pollutants, forest vegetation and soil environmental conditions were surveyed. The vegetation can be divided into 10 types by $Z\ddot{u}rich$-Montpellier school's method. Pearson coefficients between vegetation type and water quality were correlated with dissolved oxygen (DO) in the Quercus variabilis community at the 5% level and total phosphorus (TP) in the Larix leptolepis plantation at the 1% level. Especially total phosphorous and total nitrogen increased in small basins where the proportion of cultivated and residential area increased. The analysis of influences of pollutant discharge on water quality showed that pollutant charge was very low in forest land area ($Y_{T-P}$=-0.0017X+0.2215, r=0.16, $Y_{COD}$=- 0.0395X+8.5051 r=0.47). The soil types of western area were comparatively simple, but those of eastern area were complicated with regosols, red-yellow soils, lithosoles, etc. The pH, total solid (TS) and volatile substance (VS) of the forest and agricultural land soils collected in each site were 5.4~6.9, 75.8~80.2%, and 3.80%~5.80%, respectively. According to the analytical result of soil environmental conditions, heavy metal contents fell short to the mean value of natural conditions. Runoff amount (Y) and depth of topsoil (X) were negatively correlated, $Y_{ron}=-1.0088X_{top}+35.378$ (r=0.68). The correlation was much lower in up-stream but much higher in down-stream, because permeation into soil particle was larger on down-stream due to its more or less gentle slope. Pearson coefficients between soil pH and water pH were statistically significant at 1% level.