• The Journal of Advanced Prosthodontics
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• v.14 no.3
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• pp.173-181
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• 2022

PURPOSE. This analysis aimed to evaluate the intaglio surface trueness, antagonist's wear volume loss, and fracture resistance of full-contour crowns of (Y, Nb)-stabilized fully-sintered zirconia (FSZ), 4 mol% or 5 mol% yttria-stabilized partially sintered zirconia (4YZ or 5YZ) with high-speed sintering. MATERIALS AND METHODS. A total of 42 zirconia crowns were separated into three groups: FSZ, 4YZ, and 5YZ (n = 14). The intaglio surface trueness of the crowns was evaluated at the inner surface, occlusal, margin, and axial areas and reported as root-mean-square, positive and negative average deviation. Half of the specimens were aged for 120,000 cycles in the chewing simulator, and the wear volume loss of antagonist was measured. Before and after chewing, the fracture load was measured for each group. The trueness values were analyzed with Welch's ANOVA, and the wear volume loss with the Kruskal-Wallis tests. Effect of the zirconia type and aging on fracture resistance of crowns was tested using two-way ANOVA. RESULTS. The intaglio surface trueness measured at four different areas of the crown was less than 50 ㎛, regardless of the type of zirconia. No significant P in wear volume loss of antagonists were detected among the groups (P > .05). Both the type of zirconia and aging showed statistically significant effects on fracture resistance (P < .05). CONCLUSION. The full-contour crowns of FSZ as well as 4YZ or 5YZ with high-speed sintering were clinically acceptable, in terms of intaglio surface trueness, antagonist's wear volume loss, and fracture resistance after simulated mastication.

• Journal of Pharmacopuncture
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• v.10 no.1 s.22
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• pp.85-100
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• 2007

Objectives : This research was executed to verify antitumor effect and protective effect on doxorubicin(Doxo)-induced toxicity of Cultivated Wild Ginseng(CWG) and synergic effect of CWG with Doxo in B16/F10 melanomas-bearing C57BL/6 mice. Methods : To evaluate protective effect on doxorubicin(Doxo)-induced toxicity and enhancing effect on the antitumor activity of Doxo, CWG water extract(0.5 ml) was intraperitoneally injected for 10 days, in combination with intraperitoneal injection of Doxo(4 mg/kg) on days 12, 16, 19, to mice subcutaneously inoculated with $2{\times}10^6/ml$ B16/F10 melanoma cells. In order to investigate antitumor effect of CWG, CWG water extract(0.5 ml) was intraperitoneally injected for 10 days to mice subcutaneously inoculated with $2{\times}10^6/ml$ B16/F10 melanoma cells. Results : The body weights of melanoma-bearing mice increased following B16/F10 cells inoculation. In contrast, such an increase in body weights was significantly attenuated by Doxo administration. Whereas CWG inhibits the decrease in body weights induced by Doxo. The tumor volume and tumor weights of melanomas-bearing mice dramatically increased following B16/F10 cells inoculation, In contrast, such an increase in tumor volume and tumor weights were significantly attenuated by Doxo or CWG administration. But the synergic effect of CWG with Doxo was not observed. The reduction of cellularity of seminiferous epithelia, level of spermatogonium and spermatid induced by Doxo was recovered by CWG administration. BrdU labeling index of spermatogonium was remarkably decreased in Doxo group but was no change in CWG group. Whereas the incidence and intensity of BrdU labelled spermatocytes and spermatids were increased by CWG administration than those of Doxo group. Conclusions : The obtained results suggest that CWG have antitumor effect and protective effect on doxo-induced testicular toxicity. This effect might be mediated through the supplementation of vital energy.

• Steel and Composite Structures
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• v.18 no.1
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• pp.235-253
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• 2015

In this research, a simple but accurate sinusoidal plate theory for the thermomechanical bending analysis of functionally graded sandwich plates is presented. The main advantage of this approach is that, in addition to incorporating the thickness stretching effect, it deals with only 5 unknowns as the first order shear deformation theory (FSDT), instead of 6 as in the well-known conventional sinusoidal plate theory (SPT). The material properties of the sandwich plate faces are assumed to vary according to a power law distribution in terms of the volume fractions of the constituents. The core layer is made of an isotropic ceramic material. Comparison studies are performed to check the validity of the present results from which it can be concluded that the proposed theory is accurate and efficient in predicting the thermomechanical behavior of functionally graded sandwich plates. The effect of side-to-thickness ratio, aspect ratio, the volume fraction exponent, and the loading conditions on the thermomechanical response of functionally graded sandwich plates is also investigated and discussed.

• The Journal of Korean Medicine
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• v.27 no.2 s.66
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• pp.70-85
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• 2006

Objectives; This study examined the neuroprotective effect of Hyulbuchookautang (血府逐瘀湯, HBCAT)against neural damage following focal cerebral infarction. Methods : Sprague-Dawley Rats were induced with focal cerebral infarction by temporal middle cerebral artery occlusion (MCAO). The rats were divided into 2 groups. We treated extract of HBCAT to one group after operation (sample group), and the other group wasn't treated after operation (control group). We observed neurological scores and TIC-stained infarct area, total infarct volume in brain sections and Bax-positive neurons, HSP70- positive neurons in brain regions. Results : HBCAT treatment at 3 days after MCAO reduced neurological scores induced by MCAO. HBCAT treatment at 5 days after MCAO reduced TTC-stained infarct area in brain sections induced by MCAO. HBCAT treatment at 5 days after MCAO reduced total infarct volume in brain sections induced by MCAO. HBCAT treatment after MCAO reduced Bax-positive neurons in cortex infarct core and cortex infarct penumbra and caudo-putamen of brain regions induced by MCAO. HBCAT treatment after MCAO reduced HSP70- positive neurons in cortex infarct penumbra of brain regions induced by MCAO. Conclusions : These results suggest that HBCAT has a neuroprotective effect against focal cerebral ischemia.

• Asian Journal of Turfgrass Science
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• v.16 no.1
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• pp.41-47
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• 2002

For this study grasp quantitative humidity variation with planting stratification to various green space of calculation method, observed humidity distribution in the green space. with this data, coverage condition and humidity distribution, planting calculation method and humidity, planting stratification calculation method and humidity, analyzed by revolution analysis. In this result, as well as coverage condition, planting stratification effect humidity variation. increasing planting ratio (area) and planting volume (capacity) effect higher humidity. especially, if we compared between planting stratification calculation method and higher humidity, effect by a revolution coefficient and a correlation coefficient, effect relatively planting volume (capacity) higher than stratification ratio (area). today, in the index of higher humidity, planting calculation propose application of capacity method.

• Journal of Korean Medicine Rehabilitation
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• v.19 no.3
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• pp.1-13
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• 2009

Objectives : This study evaluates neuroprotective effect of Gastrodiae Rhizoma on apoptosis in the cerebral infarct. Methods : Cerebral infarct was induced by the middle cerebral artery occlusion (MCAO) for 2 hours with intraluminal thread method in Sprague-Dawley rats. Then ethanol extract of Gastrodiae Rhizoma was administered orally for 3 days. Infarct area and volume were evaluated with TTC staining. Neuronal apoptosis was identified with TUNEL labeling. Apoptosis modulatory effect was observed with immunohistochemical Bax, Bcl-2, iNOS, and MMP-9 expressions in penumbra. Results : 1. Ethanol extract of Gastrodiae Rhizoma reduced infarct size partly and volume significantly of in the MCAO rat brain. 2. Ethanol extract of Gastrodiae Rhizoma reduced TUNEL positive cell ratio in the penumbra of MCAO rat brain significantly. 3. Ethanol extract of Gastrodiae Rhizoma suppressed Bax, iNOS and MMP-9 expression in the penumbra of MCAO rat brain significantly. 4. Ethanol extract of Gastrodiae Rhizoma did not change Bcl-2 expression in the penumbra of MCAO rat brain. But expression ratio of Bcl-2 against Bax was increased in the Gastrodiae Rhizoma group. Conclusions : These results suggest that Gastrodiae Rhizoma plays an anti-apoptotic neuroprotective effect through suppression of Bax, iNOS, and MMP-9 expressions and relative up-regulation of Bcl-2 in the ischemic brain tissue.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.4
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• pp.561-566
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• 2015

In this study, the effect of temperature effect of the rubber matrix filled with nano sized silica particles composites with silica volume fraction of 19-25% was investigated by the Charpy impact test. The Charpy impact test was conducted in the temperature range from $-40^{\circ}C$ to $0^{\circ}C$. The critical energy release rate GIC of the rubber matrix composites filled with nano sized silica particles was considerably affected by temperature and it was shown that the maximum value was appeared at higher temperature between temperature tested and it was shown that the value of GIC increases as temperature tested increases. The major fracture mechanisms were matrix deformation, silica particle debonding and delamination, microcrack between particles and matrix, and/or pull out between particles and matrix which is ascertained by SEM photographs of Charpy impact surfaces fracture.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.6
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• pp.843-848
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• 1996

As the first step of studies related to production of chitooligosaccharides by physical methods, chitosan solution were sonicated with 20 kHz and various treatment effects were examined to present fundamental data of sonicated chitosan solution. Intrinsic viscosity of chitosan solution sharply decreased from 3.76 dl/g to 2.90 dl/g until 5 minutes of sonication and then slowly decreased. With low volume of chitosan solution, sonication was very effective and temperature of chitosan solution slightly affected the efficiency of sonication. In case of changing the solvent, no significant differences were observed on the effect of sonication, however, acetate buffer had highest sonication effect among various solvents. The sonication effect was increased as the increasement of the value of pH, on the contrary, ionic strength and type of counterions showed no effect on sonication. With these results, we assumed that optimal sonication treatment would be as follows, solution volume was $10\~20\;ml$, temperature range was $20\~30^{\circ}C$, pH value of solution was 4.5 and type of solvent was acetate buffer.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.34 no.3
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• pp.53-58
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• 2002

This paper was performed to investigate the effect of pore structure on ink residual behavior. To prepare different coating structures as substrates against inks, fine, medium and coarse calcium carbonate were used in the coating color. It is well known ink properties can affect to print qualities. After printing on the coated paper, ink layer can consider as third structure addition to paper and coating layer. To compare effect of ink properties on the surface structure and print qualities, several properties of ink were also adopted as raw material. Particle size of pigment effect on gloss evaluation of coated paper increased with calendering. It was shown that ink transfer rate increased as surface of the sample was smooth. The ink contained low viscosity resin evaluated more print gloss. Finer pigment particle size, smaller pore size and higher porosity. Pore volume of coated paper was slightly decreased with printing as the coating was prepared with the finest particle size. However, it founded that ink resin could not affect on pore volume and distribution of printed paper

• Computers and Concrete
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• v.26 no.1
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• pp.31-52
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• 2020

This paper investigates the size dependent effect on the vibration analysis of a porous nanocomposite viscoelastic plate reinforced by functionally graded-single walled carbon nanotubes (FG-SWCNTs) by considering nonlocal strain gradient theory. Therefore, using energy method and Hamilton's principle, the equations of motion are derived. In this article, the effects of nonlocal parameter, aspect ratio, strain gradient parameter, volume fraction of carbon nanotubes (CNTs), damping coefficient, porosity coefficient, and temperature change on the natural frequency are perused. The innovation of this paper is to compare the effectiveness of each mentioned parameters individually on the free vibrations of this plate and to represent the appropriate value for each parameter to achieve an ideal nanocomposite plate that minimizes vibration. The results are verified with those referenced in the paper. The results illustrate that the effect of damping coefficient on the increase of natural frequency is significantly higher than the other parameters effect, and the effects of the strain gradient parameter and nonlocal parameter on the natural frequency increase are less than damping coefficient effect, respectively. Furthermore, the results indicate that the natural frequency decreases with a rise in the nonlocal parameter, aspect ratio and temperature change. Also, the natural frequency increases with a rise in the strain gradient parameter and CNTs volume fraction. This study can be used for optimizing the industrial and medical designs, such as automotive industry, aerospace engineering and water purification system, by considering ideal properties for the nanocomposite plate.