• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.2
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• pp.280-289
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• 2004

Adequate polymerization is a crucial factor in obtaining optimal physical properties and clinical performance of resin composite restorative materials. The purpose of this study was to determine the effectiveness of shade and depth on dental composite resin polymerized with plasma arc curing unit employing FTIR and microhardness. From this experiment, the following results were obtained : 1. The light transmission and microhardness by mode 6 in plasma arc curing were similar to by 20 secs in halogen light curing. 2. The experimental groups of A1, A2, A3, A3.5 were not signifcant difference to light transmission and microhardness on surface and 2mm depth, but were significant difference on 3mm and 4mm depth. Especially light transmission and microhardness were small in darker shade and deeper thickness. 3. Compared with depth cure, uncured monomer amount increased at more than 2mm depth. 4. The light transmission by FTIR and polymerization by microhardness were significant corelation.

• Bulletin of the Korean Chemical Society
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• v.34 no.10
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• pp.2889-2894
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• 2013

A new complex [$Ni(phen)(C_9H_8Br_2NO_3)_2{\cdot}2CH_3OH{\cdot}2H_2O$] [phen: 1,10-phenanthroline $C_9H_8Br_2NO_3$: 3,5-dibromo-L-tyrosine] was synthesized and characterized by IR, elemental analysis and single crystal X-ray diffraction. X-ray crystallography shows that Ni(II) ion is six-coordinated. The Ni(II) ion coordinates with four nitrogen atoms and two oxygen atoms from three ligands, forming a mononuclear Ni(II) complex. The crystal crystallizes in the Orthorhombic system, space group $P2_12_12$ with a = 12.9546 ${\AA}$, b = 14.9822 ${\AA}$, c = 9.9705 ${\AA}$, V = 1935.2 ${\AA}$, Z = 1, F(000) = 1008, S = 0.969, ${\rho}_{calcd}=1.742g{\cdot}cm^{-3}$, ${\mu}=4.688mm^{-1}$, $R_1$ = 0.0529 and $wR_2$ = 0.0738 for 3424 observed reflections (I > $2{\sigma}(I)$). Theoretical study of the title complex was carried out by density functional theory (DFT) method and the B3LYP method employing the $6-3l+G^*$ basis set. The energy gap between HOMO and LUMO indicates that this complex is prone to interact with DNA. CCDC: 908041.

• Restorative Dentistry and Endodontics
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• v.42 no.3
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• pp.206-215
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• 2017

Objectives: To determine the combined effect of fatigue cyclic loading and thermocycling (CLTC) on the shear bond strength (SBS) of a resin cement to zirconia surfaces that were previously air-abraded with aluminum oxide ($Al_2O_3$) particles at different pressures. Materials and Methods: Seventy-two cuboid zirconia specimens were prepared and randomly assigned to 3 groups according to the air-abrasion pressures (1, 2, and 2.8 bar), and each group was further divided into 2 groups depending on aging parameters (n = 12). Panavia F 2.0 was placed on pre-conditioned zirconia surfaces, and SBS testing was performed either after 24 hours or 10,000 fatigue cycles (cyclic loading) and 5,000 thermocycles. Non-contact profilometry was used to measure surface roughness. Failure modes were evaluated under optical and scanning electron microscopy. The data were analyzed using 2-way analysis of variance and ${\chi}^2$ tests (${\alpha}=0.05$). Results: The 2.8 bar group showed significantly higher surface roughness compared to the 1 bar group (p < 0.05). The interaction between pressure and time/cycling was not significant on SBS, and pressure did not have a significant effect either. SBS was significantly higher (p = 0.006) for 24 hours storage compared to CLTC. The 2 bar-CLTC group presented significantly higher percentage of pre-test failure during fatigue compared to the other groups. Mixed-failure mode was more frequent than adhesive failure. Conclusions: CLTC significantly decreased the SBS values regardless of the air-abrasion pressure used.

• Korean Journal of Microbiology
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• v.42 no.2
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• pp.103-110
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• 2006

T-RFLP analysis and clone sequencing analysis based on bacterial 16S rDNA were conducted to assess bacterial community structure and diversity in Zoysia japonica soil treated with liquid fertilizer containing amino acids(LFcAA) after spray with herbicide. The results of T-RFLP (terminal restriction fragment length poly-morphism) analysis using restriction enzyme Hae III showed that the T-RFs of various size appeared evenly in the 32 clones of KD3 and 38 clones of KD4 respectively that had been treated with liquid fertilizer containing amino acid(LFcAA) compared to 23 clones of KD2 hat had not been treated with LFcAA. The microbial com- munity structure in KD2 appeared less diverse than those in KD3 and KD4. Analysis of partial sequences for 110 clones from KDI (control), KD2 (non-treated), KD3 (LFcAA 1X), KD4 (LFcAA 2X), respectively, revealed that most bacteria were related with uncultured bacteria in a 16S rDNA sequence similarity range of 91-99% through blast search. Otherwise, the other clones were members of proteobacteria, Acidobacteria, Act-inobacteria, Sphingobacteria and Planctomyces groups. Especially in KD4, members of Alpha Proteobacteria, Rhizobiales, Sphigomonadales, Caulobacterales, Gamma Proteobacteria, the genus Pseudomonas, Betapro-teobacteria, Nitrosomonadales and genus Nitrosospira appeared to be dominant. In addition, Acidobacteria group, Actinobacteria group, Planctomycetacia and Sphingobacteria were also shown. The microbial com-munity structure in Z. japonica soil sprayed with herbicide was affected by LFcAA.

• Journal of Marine Bioscience and Biotechnology
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• v.15 no.2
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• pp.82-89
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• 2023

Microalgae, as photosynthetic organisms, possess the ability to produce a diverse array of bioactive compounds. This study focused on the transformant Chlamydomonas reinhardtii dZL and subjected it to cultivation under varying light intensities (60, 120, 180, and 240 µmol/m²/s). Our aim was to assess the impact of light intensity on both microalgal biomass and carotenoid production. The cultivation took place in 80 mL bubble column photobioreactors, specifically the Multi-cultivator. Notably, the culture exposed to 240 µmol/m²/s exhibited the most rapid cell growth, surpassing even the cell concentration achieved at 180 µmol/m²/s by day 8. A detailed analysis of the specific irradiance rate over time unequivocally revealed a sharp decline in growth rates when the rate fell below 2 × 10^-10 µmol/cell/s. Although the culture with 60 µmol/m²/s yielded the highest carotenoid content (1.2% of dry weight), the culture exposed to 240 µmol/m²/s recorded the highest carotenoid concentration at 8.9 mg/L owing to its higher biomass. Our findings reveal the critical importance of maintaining a specific irradiance rate above 2 × 10^-10 µmol/cell/s to enhance biomass and carotenoid productivity. This study lays the groundwork for defining optimal light intensity conditions applicable to mass culture systems, with the objective of augmenting C. reinhardtii biomass and optimizing carotenoid productivity.

• Korean Journal of Digital Imaging in Medicine
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• v.15 no.2
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• pp.55-61
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• 2013

The purpose of this study is to evaluate image blurring according to variation of the ETL and propose the clinically appropriate ETL range. SIEMENS MAGNETOM Skyra 3.0T and 20 channel head coil were used for the study. MRI phantom was kept the lines horizontally to three direction(X,Y,Z) of the coil and T1, T2 weighted images that used the fast spin echo technique acquired. The ETL with increase of 10 was applied from 10 to 80. In addition, the ETL with increase of 1 was applied in the interval statistically significant differences occurred. And T1, T2 weighted images that used the conventional spin echo technique acquired to compare image blurring of the images that used the fast spin echo technique. The slope of lattice in the images was measured using Image J 1.47v program to evaluate image blurring. And image blurring was determined by the degree of the slope. The statistical significance of both techniques was evaluated by the Kruskal-Wallis test of the SPSS 17.0v. And the correlation of the ETL and image blurring was evaluated quantitatively by regression analysis. The slope of the T1, T2 weighted images that used fast spin echo technique decreased as contrasted with conventional spin echo technique. In the result of the Kruskal-Wallis test, the T1, T2 weighted images that used fast spin echo technique made a significant difference with conventional spin echo technique. Particularly, in the Tomhane' T2 test, the T1, T2 weighted images made a significant difference from ETL 22 and 31 respectively. In the result of the regression analysis, the R-squared of the T1, T2 weighted images are 0.762 and 0.793. It is difficult to apply the long ETL in the T1 weighted image caused by the short TR and multi-slices study. Therefore, clinical impact according to variation of the ETL is very slight in the T1 weighted images. But the application of the proper ETL is demanded in T2 weighted images using the fast spin echo technique in order to prevent image blurring.

• Korean Journal of Head & Neck Oncology
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• v.18 no.2
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• pp.142-149
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• 2002

Objectve : Okadaic acid is a specific inhibitor of serine/threonine protein phosphatase 1 and 2A. In order to know the mechanism of apoptosis induced by okadaic acid, we treated FRTL-5 thyroid cells with okadaic acid and measured the changes of important proteins that are involved in apoptosis. Materials and Methods: We measured caspase 3 activity, $PLC-{\gamma}1$ degradation, the expression of XIAP, cIAP1, cIAP2, and cytochrome c release in okadaic acid-treated FRTL-5 thyroid cells. Results: Okadaic acid-induced caspase 3 activation and $PLC-{\gamma}1$ degradation and apoptosis were dose-dependent with a maximal effect at a concentration of 80 nmol and time-dependent with a maximal effect at 24 hours after treatment. The elevated caspase 3 activity in okadaic acid treated FRTL-5 thyroid cells are correlated with down-regulation of XIAP and cIAP1, but not cIAP2. General and potent inhibitor of caspases, z-VAD-fmk. abolished okadaic acid-induced caspase 3 activity and $PLC-{\gamma}1$ degradation. The release of cytochrome c in okadaic acid-induced FRTL-5 thyroid cells was dose-dependent with a maximal effect at a concentration of 80 nmol. Conclusions: These findings suggest that mechanism of okadaic acid-induced apoptosis is associated with cytochrome c release and increase of caspase 3 activation in FRTL-5 thyroid cells.

• Journal of The Korean Society of Grassland and Forage Science
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• v.13 no.2
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• pp.86-92
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• 1993

The variation of the esterase isozyme, germination rate, chemical composition and digestibility of field bean(G1ycine soja S. and Z.) were estimated. The results are as follows; 1. The banding patterns of the esterase isozyme in field bean were varied with the tissue and habitat. 2. The enzyme activity of the Est-I, Est-2, Est-3 and Est-4 in field bean showed a high value compared with the other enzyme. 3. The range of germination temperature in field bean was 10-40C and the optimum germination temperature was 25- 38^{\circ}C.$. 4. The crude protein(CP) contents was 19.9% in the whole plant, 27.8% in the leaf and 45.9% in the seed, the cellulose contents was 29.5% in the whole plant, 23.0% in the leaf and 13.8% in the seed, the neutral detergent fiber(NDF) was 62.6% in the whole plant, 47.9% in the leaf and 47.9% in the seed and the acid detergent fiber(ADF) was 44.5% in the whole plant, 28.4% in the leaf and 28.4% in the seed, respectively. 5. The digestibility of the field bean was 44.1% in the whole plant, 49.6% in the leaf and 75.1% in the seed, NDF was 26.2% in the whole plant 46.2% in the leaf, ADF was 29.0% in the whole plant, 47.7% in the leaf and 58.0% in the seed and Cellulose was 48.7% in the whole plant, 58.0% in the leaf and 70.2% in the seed, respectively. 6. Total digestible nutrients(TDN) of the field bean was 47.4% in the whole plant, 51.5% in the leaf and 70.2% in the seed, respectively. The digestible energy(DE) value was 2.1 kcal/g in the whole plant, 2.27 kcal/g in the leaf and 3.10 kcal/g in the seed and the metabolizable energy(ME) value was 1.72 kcal/g in the whole plant, 1.86 kcal/g in the leaf and 3.23 kcal/g in the seed, respectively.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.37 no.1
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• pp.24-34
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• 2001

The authors reconstruct a mooring type underwater positioning system to measure the movement of bag-net in a set-net by long base line mode with four transponders attached on the bag-net in latitudinal and a transponder fixed on the sea bed. To confirm the practical use of the system, the field experiments were carried out at the Jaran Bay, Kosung, Kyungnam Prov., on October 6, 2000 (neap tide) and November 28, 2000 (spring tide). And the vertical oscillation of bag-net was observed with three data loggers attached on the bottom of bag-net in longitudinal on November 28, 2000. The longitudinal movement range, the latitudinal one and the vertical one of the bag-net were 3.2 m, 3.4 m and 2.1 m. respectively. At the spring tide, these variations were 7.8 m, 7.8 m and 5.0 m, respectively. The vertical oscillation range about the bottom of the bag-net at near point of the slope net, at the middle part and at far point from the slope net were 3.2 m, 3.7 m and 8.4 m, respectively. The depth of the bottom net was decreased and its vertical oscillation appeared frequently when the current speed was more than 10 cm/s and the current direction was significantly different from the longitudinal axis of the bag-net. The variation of hydrophone coordinates measured by the transponder fixed on the sea bed presents that hydrophones equipped to the frame line of the set-net could be moved within several meters due to the tidal current. The fact indicates that the compensation of hydrophone coordinates is necessary to reduce the measuring errors. The position measuring errors of x, y and z axis of the system measured in the cage of aquaculture were 0.6 m, 0.8 m, and 1.2 m, respectively. And the errors of the transponders those were close to the base lines or placed in the baselines were smaller than those of others.

• Korean Journal of Weed Science
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• v.8 no.2
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• pp.182-186
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• 1988

This study was conducted to level up the tolerance of tobacco plant against bialaphos herbicide through tissue culture. The relatively good shoot regeneration from the subcultured calli treated with bialaphos at 0.5 ppm was observed in old the tobacco varieties tested such as NC 82, BY 4 and KA 101. However, at the treatment of bialaphos 1.0 ppm, shoot regeneration was only made in KA 101 variety, showing better regeneration than that of untreated one, When these shoots were transfered to the medium containing of bialaphos 10.0 ppm, the percentage of living shoots (i.e. tolerant plant) was very low, showing 2.43% in NC 82, 2.76% in KA 101 and 0.78% BY 4. Calli were induced and multiplied from leaf petiole of the above tolerant plants even under 2.5ppm of bialaphos, showing an average of 9% in NC 82 and 16% in KA 101 as compared with the untreated control. No calli were induced from tolerant plants as bialaphos concentration increased up to 5.0 ppm. Direct shooting from leaves of the above tolerant plants, that is selected at 10.0ppm of bialaphos treatment, was observed even under 10.0ppm of bialaphos treatment both in NC 82 and in KA 101 varieties, indicating that tolerance of tobacco plants against bialaphos can be greatly increased.