• The Journal of Advanced Prosthodontics
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• v.3 no.3
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• pp.113-118
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• 2011

PURPOSE. The objective of the present study was to evaluate the effect of five different metal framework designs on the fracture resistance of the metal-ceramic restorations. MATERIALS AND METHODS. For the purpose of this study, the central incisor tooth was prepared, and the metal analogue of it and a master die were fabricated. The counter die with the 0.5 mm clearance was used for fabricating the wax patterns for the metal copings. The metal copings with five different metal framework designs were designed from Group 1 to 5. Group 1 with the metal collar, Group 2, 3, 4 and 5 with 0 mm, 0.5 mm, 1 mm and 1.5 mm cervical metal reduction respectively were fabricated. Total of fifty metal ceramic crown samples were fabricated. The fracture resistance was evaluated with the Universal Testing Machine (Instron model No 1011, UK). The basic data was subjected to statistical analysis by ANOVA and Student's t-test. RESULTS. Results revealed that the fracture resistance ranged from 651.2 to 993.6 N/$m^2$. Group 1 showed the maximum and Group 5 showed the least value. CONCLUSION. The maximum load required to fracture the test specimens even in the groups without the metal collar was found to be exceeding the occlusal forces. Therefore, the metal frameworks with 0.5 mm and 1 mm short of the finish line are recommended for anterior metal ceramic restoration having adequate fracture resistance.

• The Journal of Advanced Prosthodontics
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• v.6 no.4
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• pp.278-284
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• 2014

PURPOSE. There is insufficient data regarding the durability of porcelain laminate veneers bonded to existing composite fillings. The aim of the present study was to evaluate the fracture resistance and microleakage of porcelain laminate veneers bonded to teeth with existing composite fillings. MATERIALS AND METHODS. Thirty maxillary central incisors were divided into three groups (for each group, n=10): intact teeth (NP), teeth with class III composite fillings (C3) and teeth with class IV cavities (C4). Porcelain laminate veneers were made using IPS-Empress ceramic and bonded with Panavia F2 resin cement. The microleakage of all of the specimens was tested before and after cyclic loading ($1{\times}10^6$ cycles, 1.2 Hz). The fracture resistance values (N) were measured using a universal testing machine, and the mode of failure was also examined. The statistical analyses were performed using one-way ANOVA and Tukey post hoc tests (${\alpha}=.05$). RESULTS. There was a significant difference in the mean microleakage of group C4 compared with group NT (P=.013). There was no significant difference in the fracture loads among the groups. CONCLUSION. The microleakage and failure loads of porcelain laminate veneers bonded to intact teeth and teeth with standard class III composite fillings were not significantly different.

• The Journal of Advanced Prosthodontics
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• v.6 no.4
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• pp.317-324
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• 2014

PURPOSE. This study was to evaluate the effect of grinding of the inner metal surface during the porcelain try-in stage on metal-porcelain bonding considering the maximum temperature and the vibration of samples. MATERIALS AND METHODS. Ninety-one square prism-shaped ($1{\times}1{\times}1.5mm$) nickel-chrome cast frameworks 0.3 mm thick were prepared. Porcelain was applied on two opposite outer axial surfaces of the frameworks. The grinding was performed from the opposite axial sides of the inner metal surfaces with a low-speed handpiece with two types of burs (diamond, tungsten-carbide) under three grinding forces (3.5 N, 7 N, 14 N) and at two durations (5 seconds, 10 seconds). The shear bond strength (SBS) test was performed with universal testing machine. Statistical analyzes were performed at 5% significance level. RESULTS. The samples subjected to grinding under 3.5 N showed higher SBS values than those exposed to grinding under 7 N and 14 N (P<.05). SBS values of none of the groups differed from those of the control group (P>.05). The types of bur (P=.965) and the duration (P=.679) did not affect the SBS values. On the other hand, type of bur, force applied, and duration of the grinding affected the maximum temperatures of the samples, whereas the maximum vibration was affected only by the type of bur (P<.05). CONCLUSION. Grinding the inner metal surface did not affect the metal-porcelain bond strength. Although the grinding affected the maximum temperature and the vibration values of the samples, these did not influence the bonding strength.

• The Journal of Advanced Prosthodontics
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• v.12 no.5
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• pp.322-328
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• 2020

PURPOSE. This study evaluated the shear bond strength between 3D printed provisional resin and conventional provisional resin depending on type of conventional provisional resin and different surface treatments of 3D printed resin. MATERIALS AND METHODS. Ninety-six disc-shaped specimens (Ø14 mm × 20 mm thickness) were printed with resin for 3D printing (Nextdent C&B, Vertex-Dental B. V., Soesterberg, Netherlands). After post-processing, the specimens were randomly divided into 8 groups (n=12) according to two types of conventional repair resin (methylmethacrylate and bis-acryl composite) and four different surface treatments: no additional treatment, air abrasion, soaking in methylmethacrylate (MMA) monomer, and soaking in MMA monomer after air abrasion. After surface treatment, each repair resin was bonded in cylindrical shape using a silicone mold. Specimens were stored in 37℃ distilled water for 24 hours. The shear bond strength was measured using a universal testing machine at a crosshead speed of 0.5 mm/min. Failure modes were analyzed by scanning electron microscope. Statistical analysis was done using one-way ANOVA test and Kruskal-Wallis test (α=.05). RESULTS. The group repaired with bis-acryl composite without additional surface treatment showed the highest mean shear bond strength. It was significantly higher than all four groups repaired with methylmethacrylate (P<.05). Additional surface treatments, neither mechanical nor chemical, increased the shear bond strength within methylmethacrylate groups and bis-acryl composite groups (P>.05). Failure mode analysis showed that cohesive failure was most frequent in both methylmethacrylate and bis-acryl composite groups. CONCLUSION. Our results suggest that when repairing 3D printed provisional restoration with conventional provisional resin, repair with bis-acryl composite without additional surface treatment is recommended.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.6
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• pp.766-771
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• 2013

The purpose of this study was to investigate interaction effects of genes using a Harvester method. A sample of Korean cattle, Hanwoo (n = 476) was chosen from the National Livestock Research Institute of Korea that were sired by 50 Korean proven bulls. The steers were born between the spring of 1998 and the autumn of 2002 and reared under a progeny-testing program at the Daekwanryeong and Namwon branches of NLRI. The steers were slaughtered at approximately 24 months of age and carcass quality traits were measured. A SNP Harvester method was applied with a support vector machine (SVM) to detect significant SNPs in the CCDC158 gene and interaction effects between the SNPs that were associated with average daily gains, cold carcass weight, longissimus dorsi muscle area, and marbling scores. The statistical significance of the major SNP combinations was evaluated with $x^2$-statistics. The genotype combinations of three SNPs, g.34425+102 A>T(AA), g.4102636T>G(GT), and g.11614-19G>T(GG) had a greater effect than the rest of SNP combinations, e.g. 0.82 vs. 0.75 kg, 343 vs. 314 kg, 80.4 vs $74.7cm^2$, and 7.35 vs. 5.01, for the four respective traits (p<0.001). Also, the estimates were greater compared with single SNPs analyzed (the greatest estimates were 0.76 kg, 320 kg, $75.5cm^2$, and 5.31, respectively). This result suggests that the SNP Harvester method is a good option when multiple SNPs and interaction effects are tested. The significant SNPs could be applied to improve meat quality of Hanwoo via marker-assisted selection.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.14
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• pp.5869-5873
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• 2015

Background: Breast and cervical cancers are among the most frequent and most fatal cancers in women. Life span of patients may be increased and quality of life improved through early diagnosis and treatment. This investigation was performed in order to determine knowledge and practices of female health personnel working at a university hospital regarding breast and cervical cancers. Materials and Methods: This descriptive investigation was performed in Erciyes University Hospitals in 2014. A total of 524 female health personnel were included in the study. Data were collected through a questionnaire of 36 questions prepared by the researchers. The Chi square test and logistic regression were used for statistical analyses. Results: The mean age of the study group was $32.8{\pm}6.9$ years, 18.3% being doctors and 81.7% nurses. Of the study group, 60.5% stated that they performed self breast-examination, 4.4% underwent HPV testing, 26.3% thought about taking an HPV test, 34.7% of those who are 40 years and over had mammography regularly and 19.5% of those who were married had a Pap smear conducted regularly. Most important causes of not performing the methods for early diagnosis of breast and cervical cancers are "forget and neglect". Conclusions: It was concluded that female doctors and nurses do not pay sufficient attention to screening programs for breast and cervical cancers. The importance of early diagnosis and treatment should be emphasized during the undergraduate education and in-service training programs. Health condition of personnel and their utilization of preventive health care should be followed by occupational physicians.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.8
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• pp.3383-3389
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• 2014

Background: Prostate cancer is rapidly increasing in Korea and professional societies have requested adding prostate specific antigen (PSA) testing to the National Cancer Screening Program (NCSP), but this started a controversy in Korea and neutral evidence on this issue is required more than ever. The purpose of this study was to provide economic evidence to the decision makers of the NCSP. Materials and Methods: A cost-utility analysis was performed on the adoption of PSA screening program among men aged 50-74-years in Korea from the healthcare system perspective. Several data sources were used for the cost-utility analysis, including general health screening data, the Korea Central Cancer Registry, national insurance claims data, and cause of mortality from the National Statistical Office. To solicit the utility index of prostate cancer, a face-to-face interview for typical men aged 40 to 69 was conducted using a Time-Trade Off method. Results: As a result, the increase of effectiveness was estimated to be very low, when adopting PSA screening, and the incremental cost effectiveness ratio (ICER) was analyzed as about 94 million KRW. Sensitivity analyses were performed on the incidence rate, screening rate, cancer stage distribution, utility index, and treatment costs but the results were consistent with the base analysis. Conclusions: Under Korean circumstances with a relatively low incidence rate of prostate cancer, PSA screening is not cost-effective. Therefore, we conclude that adopting national prostate cancer screening would not be beneficial until further evidence is provided in the future.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.3
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• pp.1225-1234
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• 2013

According to the importance of greenhouse gas emissions, it grows day by day, the goverment is promoting to prepare the specific policy implementation to enhance building energy-saving design standars as the development agenda. In this study, the statistical analysis was performed by Descriptive statistics, Regression analysis, and Hypothesis testing to collect to generate and storage energy usage data in real time to settle parameter setting to affect energy consumption under energy-guzzling apartment not single building. This study is expected to be utilized as the basis for the optimum energy-saving design of the future of the building or facility energy costs rise and the demand for energy-efficient and stable management.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.9
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• pp.1109-1116
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• 2013

This study aims to investigate the spatial randomness of fatigue crack growth rate for the friction stir welded (FSWed) 7075-T651 aluminum alloy joints. Our previous fatigue crack growth test data are adopted in this investigation. To clearly understand the spatial randomness of fatigue crack growth rate, fatigue crack growth tests were conducted under constant stress intensity factor range (SIFR) control testing. The experimental data were analyzed for two different materials-base metal (BM) and weld metal (WM)-to investigate the effects of spatial randomness of fatigue crack growth rate and material properties, the friction stir welded (FSWed) 7075-T651 aluminum alloy joints, namely weld metal (WM) and base metal (BM). The results showed that the variability, as evaluated by Weibull statistical analysis, of the WM is higher than that of the BM.

• CELLMED
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• v.2 no.1
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• pp.10.1-10.6
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• 2012

Acupuncture works by stimulating peripheral sensory nerves and their endings causing an increase in cutaneous blood flow and microcirculation, as well as release of neurotransmitters, neuropeptides, and hormones. SP6 Patch is a nanoscale nontransdermal device that mildly stimulates Stomach 36 (zusanli) and other acupuncture points. As stimulation of these points has been indicated to have an effect on hypothalamic function, it is of great research interest to investigate the effect of SP6 Patch on the physiology of organs that are affected by hypothalamic regulation. Bioelectrical tissue impedance data indicative of cellular physiologic organ function, using an Electro Interstitial Scan (EIS) system, were acquired from hypothalamus, pancreas, liver, intestines, kidneys, thyroid and adrenal glands in 10 (1 male, 9 females) volunteers while wearing the SP6 Patch daily for 1 week. EIS testing was performed at baseline with no patch, 30 min after wearing the patch, and after wearing the patch 12 h/day for 1 week. Subjects were instructed to keep well hydrated during the study period. All subjects served as their own control. The hypothesis was: The SP6 Patch worn 12 h/day on the Stomach 36 acupuncture point for 1 week, may significantly improve cellular physiologic functional status of different organs measured by EIS. All tested organs achieved significant improvement in their functional physiologic status after wearing the SP6 Pach 12 h/day for 1 week compared to baseline with an overall average statistical power > 89%. Based upon these results the hypothesis was accepted as true.