• Restorative Dentistry and Endodontics
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• v.36 no.5
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• pp.385-396
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• 2011

Objectives: This study evaluated the effects of adhesion variables such as the priming concepts of canal wall and the curing modes of adhesives on the sealing ability of a resin-based root canal filling system. Materials and Methods: Apical microleakage of the Resilon-RealSeal systems filled with 3 different combinations of adhesion variables was compared with the conventional gutta-percha filling using a dye penetration method. Experimental groups were SEDC, Resilon (Resilon Research LLC) filling with self-etch RealSeal (SybronEndo) primer and dual-cure RealSeal sealer; NELC, Resilon filling with no etching, Scotchbond Multi-Purpose (3M ESPE) primer application and light-curing adhesive; and TELC, Resilon filling with Scotchbond Multi-Purpose primer and adhesive used under total etch / wet bonding and lightcure protocols. GPCS, gutta-percha filling with conventional AH26 plus sealer, was the control group. Results: The median longitudinal dye penetration length of TELC was significantly shorter than those of GPCS and SEDC (Kruskal-Wallis test, p < 0.05). In the cross-sectional microleakage scores, TELC showed significant differences from other groups at 2 to 5 mm from the apical foramen (Kruskal-Wallis test, p < 0.05). Conclusions: When a resin-based root canal filling material was used, compared to the self-etching primer and the dual-cure sealer, the total etch/wet-bonding with primer and light-curing of adhesive showed improved apical sealing and was highly recommended.

• Proceedings of the KACD Conference
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• 2008.05a
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• pp.198-203
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• 2008

The purpose of this study was to compare the sealing abilities of four endodontic temporary restorative materials using a methylene blue dye penetration test under dynamic loading. Standardized access cavities were prepared in forty-four intact human permanent molar teeth, and the cavities were restored with Caviton, MD-Temp, IRM, or ZOE. After thermocycling, an intermittent load of 98 N at 1 Hz was applied for 1,000 cycles to the long axis of the functional cusp of each of the teeth, which were immersed in a 1% methylene blue solution. The teeth were split in half, and the linear depth of dye penetration was evaluated according to the criteria. The results were analyzed using one-way ANOVA (p = 0.05) and Duncan's multiple range test. The results demonstrated that Caviton and MD-Temp showed significantly lower microleakage than IRM and ZOE. It was concluded that Caviton and MD-Temp exhibited better sealing ability than IRM and ZOE under dynamic loading.

• Restorative Dentistry and Endodontics
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• v.33 no.3
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• pp.198-203
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• 2008

The purpose of this study was to compare the sealing abilities of four endodontic temporary restorative materials using a methylene blue dye penetration test under dynamic loading. Standardized access cavities were prepared in forty-four intact human permanent molar teeth, and the cavities were restored with Caviton, MD-Temp, IRM, or ZOE. After thermocycling, an intermittent load of 98 N at 1 Hz was applied for 1,000 cycles to the long axis of the functional cusp of each of the teeth, which were immersed in a 1% methylene blue solution. The teeth were split in half, and the linear depth of dye penetration was evaluated according to the criteria. The results were analyzed using one-way ANOVA (p = 0.05) and Duncan's multiple range test. The results demonstrated that Caviton and MD-Temp showed significantly lower microleakage than IRM and ZOE. It was concluded that Caviton and MD-Temp exhibited better sealing ability than IRM and ZOE under dynamic loading.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.6
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• pp.573-582
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• 2021

In this study, a series of processes for evaluating the effective protection against barriers that should be equipped in institutions that perform reliability tests on high-risk ammunition, such as high-explosive ammunition, were introduced. The impact that high-explosive bombs can have on personnel includes damage to the eardrum and lungs caused by explosion overpressure and penetrating wounds that can be received by fragments generated simultaneously with the explosion. Therefore, a high-explosive with COMP B explosives as its contents were set up, and an explosion protection theory investigation to calculate the degree of damage, numerical calculations and simulations were performed to verify the protection power. A numerical calculation revealed the maximum explosion overpressure on the protective wall when the high-explosive exploded and the penetration force of the fragment against a 50 mm-thick protective wall to be 77.74 kPa and 41.34 mm, respectively. In the simulation verification using AUTODYN, the maximum explosion overpressures affecting the firewall and personnel were 56.68 kPa and 18.175 kPa, respectively, and the penetration of fragments was 35.56 mm. This figure is lower than the human damage limit, and it was judged that the protective power of the barrier would be effective.

• Journal of the Ergonomics Society of Korea
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• v.32 no.2
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• pp.207-215
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• 2013

Objective: This study aimed to investigate important human factors that should be considered when developing ultra-high definition TVs by reviewing measurement methods and main characteristics of ultra-high definition displays. Background: Although much attention has been paid to high-definition displays, there have been few studies for systematically evaluating human factors. Method: In order to determine human factors to be considered in developing human-friendly displays, we reviewed subjective and objective measurement methods to figure out the current limitations and establish a guideline for developing human-centered ultra-high definition TVs. In doing so, pros and cons of both subjective and objective measurement methods for assessing humans factors were discussed and specific aspects of ultra-high definition displays were also investigated in the literature. Results: Hazardous effects such as visually-induced motion sickness, visual fatigue, and mental fatigue in the brain caused by undesirable TV viewing are induced by not only temporal decay of visual function but also cognitive load in processing sophisticated external information. There has been a growing evidence that individual differences in visual and cognitive ability to process external information can make contrary responses after exposing to the same viewing situation. A wide vision, ultra-high definition TVs provide, can has positive and negative influences on viewers depending on their individual characteristics. Conclusion: Integrated measurement methods capable of considering individual differences in human visual system are required to clearly determine potential effects of super-high vision displays with a wide view on humans. All of brainwaves, autonomic responses, eye functions, and psychological responses should be simultaneously examined and correlated. Application: The results obtained in this review are expected to be a guideline for determining optimized viewing factors of ultra-high definition displays and accelerating successful penetration of the next-generation displays into our daily life.

• Journal of Forest and Environmental Science
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• v.29 no.1
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• pp.29-37
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• 2013

The study was carried out in two different forest types viz., Banj oak and Chir pine forests to assess the variation in forest species composition and soil properties along altitudinal gradients in the Garhwal Himalayas. The results of the study showed that between the forests soil moisture was higher in Banj oak forest because of closed canopy and dense forest compared to Chir pine forest. The sand particles were reported higher in Banj oak forest which might be due to the addition of organic matter favouring coarse structure of soil, helping in holding maximum water in soils. However in the Chir pine forest low amount of soil organic matter and presence of clayey soil, develops soil compactness which reduces the penetration of water resulting in high soil bulk density. The higher accumulation of litter and presence of moisture in Banj oak forest favours higher nutrient level of nitrogen, phosphorus and potassium compared to Chir pine forest. The soil organic carbon also reduced with increasing altitude at both gradients. While bulk density has reverse trend with soil organic carbon in both the forests at different peaks of same region. In Banj oak forest, the highest density and total basal cover was reported 1,100 tree $ha^{-1}$ and 58.86 $m^2\;ha^{-1}$ respectively. However, the highest values of density and total basal cover of Chir pine forest was 560 tree$ha^{-1}$ and 56.94 $m^2\;ha^{-1}$ respectively. The total density and basal cover of both the forests reduced with increasing altitude. The study concludes that Banj oak forest has better nutrient cycling ability, well developed foest floor and has a greater protective and productive features compared to the Chir pine forest which is without lower vegetation cover and having only pine litter accumulation which does not allow any other species to grow.

• Advances in concrete construction
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• v.6 no.2
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• pp.103-121
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• 2018

This paper reports the effects of coarse and fine recycled concrete aggregates (RCA) on fresh and hardened properties of self-compacting concrete (SCC) containing ground granulated blast-furnace slag (GGBFS) as cement replacement. For this purpose, three SCC mixes groups, were produced at a constant water to binder ratio of 0.38. Both fine and coarse recycled aggregates were used as natural aggregates (NA) replacement at different substitution levels of 0%, 25%, 50%, 75% and 100% by volume for each mix group. Each group, included 0, 15% or 30% GGBFS as Portland cement replacement by weight. The SCC properties investigated were self-compactability parameters (i.e., slump flow, T500 time, V-funnel flow time, L-box passing ability and sieve stability), compressive strength, capillary water absorption and water penetration depth. The results show that the combined use of RCA with GGBFS had a significant effect on fresh and hardened SCC mixes. The addition of both fine and coarse recycled aggregates as a substitution up to 50% of natural aggregates enhance the workability of SCC mixes, whereas the addition from 50 to 100% decreases the workability, whatever the slag content used as cement replacement. An enhancement of workability of SCC mixes with recycled aggregates was noticed as increasing GGBFS from 0 to 30%. RCA content of 25% to 50% as NA replacement and cement replacement of 15% GGBFS seems to be the optimum level to produce satisfactory SCC without any bleeding or segregation. Furthermore, the addition of slag to recycled concrete aggregates of SCC mixes reduces strength losses at the long term (56 and 90 days). However, a decrease in the capillary water absorption and water permeability depth was noticed, when using RCA mixes with slag.

• Journal of Microbiology and Biotechnology
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• v.25 no.11
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• pp.1827-1834
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• 2015

The SMG1 lipase from Malassezia globosa is a newly found mono- and diacylglycerol (DAG) lipase that has a unique lid in the loop conformation that differs from the common alpha-helix lid. In the present study, we characterized the contribution of three residues, L103 and F104 in the lid and F278 in the rim of the binding site groove, on the function of SMG1 lipase. Site-directed mutagenesis was conducted at these sites, and each of the mutants was expressed in the yeast Pichia pastoris, purified, and characterized for their activity toward DAG and p-nitrophenol (pNP) ester. Compared with wild-type SMG1, F278A retained approximately 78% of its activity toward DAG, but only 11% activity toward pNP octanoate (pNP-C8). L103G increased its activity on pNP-C8 by approximately 2-fold, whereas F104G showed an approximate 40% decrease in pNP-C8 activity, and they both showed decreased activity on the DAG emulsion. The deletion of 103-104 retained approximately 30% of its activity toward the DAG emulsion, with an almost complete loss of pNP-C8 activity. The deletion of 103-104 showed a weaker penetration ability to a soybean phosphocholine monolayer than wild-type SMG1. Based on the modulation of the specificity and activity observed, a pNP-C8 binding model for the ester (pNP-C8, N102, and F278 form a flexible bridge) and a specific lipid-anchoring mechanism for DAG (L103 and F104 serve as "anchors" to the lipid interface) were proposed.

• Journal of Pharmaceutical Investigation
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• v.36 no.3
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• pp.169-174
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• 2006

The aim of this work was to prepare tenoxicam-ethanolamine salt with improved physicochemical properties for transdermal application. Tenoxicam-ethanolamine salt was prepared in methylene chloride and its physicochemical properties were investigated by DSC and FT-lR. The broad peak of tenoxicam around 3600-3200 $cm^-1$ was shifted to lower wavenumber and more broadened. The characteristic endothermic melting peak of tenoxicam appeared at $223^{\circ}C$. The melting peak of tenoxicam-ethanolamine salt was shifted to $159^{\circ}C$. In contrast to relatively small difference in the partition coefficients of tenoxicam and the tenoxicam-ethanolamine salt, large difference in aqueous solubility was observed. $Crovol^{\circledR}$ PK4O (PEG-12 palm kernel glycerides) provided the highest skin flux for both compounds. The order of the enhancing effect of the various vehicles tested was similar for tenoxicam and tenoxicam-ethanolamine salt, which indicated that their enhancing mechanism for tenoxicam and tenoxicam-ethanolamine salt is similar. Tenoxicam-ethanolamine salt had a higher skin flux than tenoxicam by 1.2- to 31.7-fold, depending on the vehicles used. It is suggested that the vehicles with medium HLB value, 1 double bond, and lower ethylene oxide chain length have a better ability to modify the permeability of the stratum corneum and to promote the effective penetration of tenoxicam and tenoxicam-ethanolamine salt.

• Journal of Periodontal and Implant Science
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• v.34 no.4
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• pp.711-722
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• 2004

The purpose of this study is to evaluate the regenerated bone histollogically using titanium reinforced ePTFE(TR-ePTFE) membrane and to investigate cell occlusiveness, wound stabilization and tissue integration of TR-ePTFE membrane. Adult male rabbits (mean BW 2kg) and TR9W (W.L.Gore&Associate.INC,USA) were used in this study. Intramarrow penetration defects were surgically created with round carbide bur(HP long #6) on calvaria of rabbits. TR-ePTFE membrane was applied to defect. Then guided bone regeneration was carried out using TR-ePTFE membrane and resorbable suture. At 2,4,8,12 weeks after the surgery, animals were sacrificed. Nondecalcified specimens were processed for histologic analysis. The result and conclusion of this study were as follows: 1. TR-ePTFE membrane had good ability of biocompatibility and cell occlusiveness. 2. space making for guided bone regenerayion was good at TR-ePTFE membrane. 3. Tissue integration was not good at TR-ePTFE membrane. So, wound stabilization was not good. 4. At 8 weeks, 12 weeks after GBR procedure, bone formation was seen. From the above results, TR-ePTFE membrane fixed tightiy on alveolar bone might be recommended for the early bone formation.