• The Journal of Advanced Prosthodontics
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• v.15 no.2
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• pp.93-100
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• 2023

PURPOSE. The aim of this study is to evaluate the effect of resin cement color, cement thickness, and thermocycling on the final color of monolithic lithium disilicate crowns. MATERIALS AND METHODS. A total of ninety prepared central incisors of typodont teeth were restored with lithium disilicate crowns which have different cement thicknesses (40 ㎛, 80 ㎛, and 120 ㎛) and cement shades (clear, yellow, and white). Color parameters of restorations were measured with a spectrophotometer in three different steps 1) before cementing 2) after cementing and 3) after thermocycling with 10000 cycles. Color differences (ΔE₀₀) were calculated with the CIEDE2000 formula and evaluated according to perceptibility (0.8) and acceptability (1.8) thresholds. The ΔE₀₀ data were analyzed by using two-way ANOVA before and after thermocycling (α = .05). RESULTS. There was no interaction between the cement shade and the cement thickness factors. After cementation, the mean ΔE₀₀ was under the perceptibility threshold in the group of 40 ㎛ cement thickness and clear cement while it was between the perceptibility and acceptability thresholds (0.8 < ΔE₀₀ < 1.8) for all other groups. After thermocycling, the ΔE₀₀ values were between the perceptibility and acceptability thresholds for all experimental groups. Although there were no significant differences among the groups, thermocycling increased the color difference values. CONCLUSION. The cementation of restorations with clear, yellow, and white resin cements resulted in color differences with uncemented restorations except for the group cemented with clear cement in 40 ㎛ cement thickness. All study groups revealed perceptible color change after thermocycling.

• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.3
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• pp.298-307
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• 2010

The purpose of this study was to assess the effect on oxygen inhibition layer(OIL) for the interfacial bonding between resin composite layers, including shear bond strength, fracture modes and degree of conversion. The first layer of specimen was filled with Z-250(shade A3) and was cured for 40s. The second layer of specimen was filled with same composite(shade A1) and was cured for 40s. The first layer of specimens for each group were prepared by methods as followings. Control(curing in atmospheric air), Group1(curing against Mylar strip), Group2(scrubbed with a acetone-soaked cotton), Group3(using Tescera light cup), Group4(using Tescera heat cup), Group5(stored in disti1led water for 30days at $37^{\circ}C$), Group6 (using bonding agent). The results were as follows: 1. There was no statistically significant different shear bond strength between control and group 1(p>0.05). 2. Group 2 showed significantly lower shear bond strength than control and group 1(p<0.05). 3. The observation of the fracture surface leads to the evidence that a major difference occurs in the case of control, group1 and group 3 samples which break mainly cohesively while the other groups break in majority adhesively. 4. The results of FTIR showed that the degree of conversion was the highest in group 2 and the lowest in control group(p<0.05). It can be concluded that an OIL is not necessary for bonding with composite resin. But if a reduced critical amount of the unreacted monomer is present, it was detrimental to bonding additional layers of composite. Further study, such as the quantitative analysis of the unreacted monomer are required.

• Archives of Pharmacal Research
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• v.27 no.7
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• pp.790-796
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• 2004

Ginseng is a shade-loving perennial herb that is cultivated mainly in Korea, Japan, and China. The ginseng root has been used as a tonic remedy, and its antidiabetic activity has been demonstrated as early as 1920s. Although wild ginseng was anecdotally thought to be superior to cultivated ginseng as far as pharmacological properties were concerned, there have been no prior reports on the antidiabetic effect of wild ginseng. In this study, we investigated the preventative anti-diabetic and anti-obese effects of wild ginseng ethanol extract (WGEE). In the preventive experiment, WGEE co-administered with a high fat diet significantly inhibited body weight gain, fasting blood glucose, triglyceride, and free fatty acid levels in a dose dependent manner. WGEE-treated mice at doses of 250 and 500 mg/kg improved the insulin resistance index by 55％ and 61％ compared to the high fat diet (HFD) control, respectively. Diameters of white and brown adipocytes were also decreased by 62％ and 46％ in the WG500-treated group compared to those in HFD fed control mice. Taken together, WGEE has potential as a preventive agent for type 2 diabetes mellitus (and possibly obesity) and deserves clinical trial in the near future.

• Asian Journal of Turfgrass Science
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• v.18 no.1
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• pp.15-27
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• 2004

For the study of ecophysiological characteristics of ground cover plant with shade tolerance, the material productivity and the growh characteristics were analyzed in Hosta clausa community at experimental farm of Kemyung College from March to October. The installation of experimental plots were split into control plot (full sunlight), 30%, 50%, 70%, shading rate by completely randomized design method. After the transplant, to take into account the edge effect of plant population, the plants were selected from each plot by random sampling every 10days. The following results were obtained; Then number of leaf, length of leaf and width of leaf length of leafstack remarkably showed high tendency under 30%, 50% shading plot as compared with control, 70% shading plot for the exmination as the process of develpment. They showed characteristics as herbaceous ground with shade tolerance under conparatively low the light condition and they ettain a stabilized development.

• Journal of The Korean Digital Architecture Interior Association
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• v.12 no.1
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• pp.45-51
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• 2012

To see sunlight condition around in storage room, this study analyzers the scope both of sunlight and of the shade of sun into upper and lower window according to seasons. For this, this study investigates sun's seasonal changes, its effect of sunlight and notes antinomic conditions for ventilation and draft performance. In this, Architects of Jangkyunggak tride to block discoloration and fading due to ultraviolet rays and visible rays and block deterioration drying of the surface of Kyung-Pan due to infrared rays by oppressing sunlight flowing by means of narrowing the area of the upper window at front face that has a direct influence of Pan-Ga to avoid the exposure to direct sunlight.

• Textile Coloration and Finishing
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• v.13 no.3
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• pp.180-187
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• 2001

Generally, polyester microfiber has much greater dye uptake than that of regular ones. In spite of high dye up-take visual shade depth of dyed fabric decreases with smaller denier, which results in poor washing fastness of dyed fabric. In this study, in order to investigate the washing fastness, polyester microfiber fabric was dyed by using two type of disperse dyes and treated with 3 different reduction clearing methods. The reduction clearing methods in this study are normal alkaline reduction clearing, $N_2$ gas replacement method, and ultrasonic treatment during reduction clearing. The results were as followings ; The most important factors affecting the washing fastness of polyester artificial suede fabric were found to be the reduction clearing method, the chemical structure of used disperse dyes and the structure and denier of fibers. It was also obtained that the heat treatment of dyed fabric decreased the washing fastness due to the dye migration from inner phase to surface.

• 한국약용작물학회:학술대회논문집
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• 2008.11a
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• pp.320-320
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• 2008

• 한국약용작물학회:학술대회논문집
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• 2008.11a
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• pp.143-144
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• 2008

• Textile Coloration and Finishing
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• v.19 no.1 s.92
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• pp.17-23
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• 2007

Dyeing properties using natural material named Sasa quelpaertensis Nakai were investigated under various conditions such as fabric type, pH, concentration, temperature, dyeing time and dipping count. Sasa quelpaertensis Nakai is a unique material in that it is raised only at Halla mountain in Jeju island and is known to have healing effect. Overall, wool fabrics were better than cotton fabrics in all aspects of the dyeing properties showing reddish yellow. For the fastness properties, robbins washing and perspiration fastness were excellent but lightfastness was poor as expected.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.10
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• pp.1644-1654
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• 2009

The concentration of dye uptake and the fastness improved when cotton and silk fabrics were treated with chitosan, a natural polymer. In this study, the effect of chitosan treatment was reviewed after the printing of cotton and silk fabrics padded with chitosan. When the change of physical and mechanical properties of printed fabrics was reviewed (as the concentration of chitosan increased) the thickness and weight increased a little, and the air permeability increased significantly than those untreated with chitosan. The dye uptake increased, accompanying a darker color shade, and the wash fastness increased 1/2-1 grade. The analysis results of enlarged images of printed patterns indicated that the width and area deformations were minimal as the concentration of chitosan increased when compared to untreated fabrics. Therefore, the dyeability and pattern quality were excellent after printing the chitosan-treated cotton and silk fabrics with cochineal dyestuff.