• Restorative Dentistry and Endodontics
• /
• v.46 no.3
• /
• pp.32.1-32.10
• /
• 2021

Objectives: This study aimed to evaluate the effect of the application method of universal adhesives on the shear bond strength (SBS) of repaired composites, applied with different thicknesses. Materials and Methods: The 84 specimens (Filtek Z350 XT) were prepared, stored in distilled water for a week and thermocycled (5,000 cycles, 5℃ to 55℃). They were roughened using 400-grit sandpapers and etched with phosphoric acid. Then, specimens were equally divided into 2 groups; Single Bond Universal (SU) and Prime&Bond Universal (PB). Each group was subdivided into 3 subgroups according to application methods (n = 14); UC: 1 coat + uncuring, 1C: 1 coat + curing, 3C: 3 coats + curing. After storage of the repaired composite for 24 hours, specimens were subjected to the SBS test and the data were statistically analyzed by 2-way analysis of variance and independent t-tests. Specimens were examined with a stereomicroscope to analyze fracture mode and a scanning electron microscope to observe the interface. Results: Adhesive material was a significant factor (p = 0.001). Bond strengths with SU were higher than PB. The highest strength was obtained from the 1C group with SU. Bonding in multiple layers increased adhesive thicknesses, but there was no significant difference in SBS values (p = 0.255). Failure mode was predominantly cohesive in old composites. Conclusions: The application of an adequate bonding system plays an important role in repairing composite resin. SU showed higher SBS than PB and the additional layers increased the adhesive thickness without affecting SBS.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.33 no.4
• /
• pp.87-98
• /
• 2015

The natural monument forests (no.374) located at Pyeongdae-ri in Jeju island are described and classified by using phytosociological methods and numerical analysis. The purpose of this paper is to identify the ecological character of Torreya nucifera forests between natural habitat and artificial habitat, as well as their spatial and phytogeographical distribution in the Korea. The comparison of forests between Pyeongdae-ri and other regions was analyzed by using a non-metric multidimensional scaling analysis (NMDS) and hierarchical clustering. On the basis of the 12 phytosociological $relev{\acute{e}}s$, the vegetation of T. nucifera dominant forest in Jeju island was arranged in one syntaxon (Alangium platanifolium-Torreya nucifera community included typicum and one subcommunity) within Camellietea. The community of T. nucifera dominant forests were characterized floristically and ecologically. We discussed diagnostic species with references, and proposed a few important diagnostic species (Ilex crenata for. microphylla, Acer palmatum, Zingiber mioga, Mercurialis leiocarpa, Osmorhiza aristata, Mecodium wrightii etc.) to explain condition of the habitat and synecological character. The communities were described by concerning their edaphical and syndynamical niche; we discussed their total distribution in Korea. In most forests they are widespread in Korean peninsular and their distribution is primarily determined by artificial plantation and periodical management. The forests consisted of T. nucifera have developed from natural environment element and artificial management. As a result they have very unique characters with the floristic, structural characterization and distribution. Furthermore, we identified that they need to apposite management for sustainability.

• Journal of Biomedical Engineering Research
• /
• v.17 no.1
• /
• pp.19-24
• /
• 1996

The purpose of this paper is to design high-order (or radial) surface gradient coil (SGC), which can provide multi-dimensional spatial selection. Although the spatial Selection with High-Order gradienT (SHOT) can provide a 2-D selection with only one selective RF pulse, the high-order gradient pro- duced by conventional cylindrical-shape coils has not been clinically useful due to the large selection size caused by the limited radial gradient intensity. However, by using the proposed high-order SGCs located near the imaging region, the size of volume selection can be reduced to a clinically useflll size of 1-2 cm in diameter by applying stronger radial gradient field with much less gradient driving power. So far radial SGCs have been designed by using the field component method and may cause distortion in the selection shapes. In this paper, by using the target field approach for the coil design, selected volumes became almost circular. A 40 cm-by-40 cm $z^2$_surface gradient coil has been designed and implemented by using the target field approach. Phantom and volunteer studies have been performed Experimental results using spatially localized MRI show good agreement to the theoretically predicted behavior.

• YAKHAK HOEJI
• /
• v.51 no.2
• /
• pp.133-139
• /
• 2007

A simple and sensitive HPLC-MS method for quantitation of 10${\alpha}$-methoxy-9,10-dihydrolysergol (MDL), the main metabolite of nicergoline, in human plasma was developed and the bioavailability parameters of MDL was assessed in Korean healthy male volunteers. Clomipramine was used as an internal standard. MDL and internal standard in plasma sample were extracted using ethyl acetate. A centrifuged upper layer was then evaporated and reconstituted with mobile phase of 10 mM ammonium acetate-acetonitrile (10 : 90, v/v). The reconstituted samples were injected into a Zorbax SB-C8 column (2.1${\times}$150 mm,5 ${\mu}$m) at a flow-rate of 0.3 ml/min. Using MS with selected ion monitoring (SIM) mode, MDL and clomipramine were detected without severe interference from human plasma matrix. MDL produced a protonated molecular ion ([M+H]$^+$) at m/z 287. Internal standard produced a protonated molecular ion ([M+H]$^+$) at m/z 315. A linear relationship for MDL was found in the range of 2.5${\sim}$100 ng/ml. The lower limit of quantitation (LLOQ) was 2.5 ng/ml with acceptable precision and accuracy. The intra- and inter-day validation for all coefficients of variation (R.S.D.%) were found less than 15%. Main pharmacokinetic parameters of 30 mg of nicergoline were revealed as follows: AUC$_t$ 321.1${\pm}$64.5 ng${\cdot}$hr/ml, C$_{max}$, 51.2${\pm}$25.3 ng/ml, T$_{max}$ 3.6${\pm}$1.5 hr, K$_{el}$ 0.12${\pm}$0.07 hr$^{-1}$ and t$_{1/2}$ 7.6${\pm}$3.4 hr. Inter subject variations and race differences were shown in comparison with the published data in the literature.

• Journal of Korean Public Health Nursing
• /
• v.30 no.2
• /
• pp.274-287
• /
• 2016

Purpose: The purpose of this study was to examine the effects of Motivational Interviewing(MI) training program on communication skill and self-efficacy of home visiting nurses(HVNs). Methods: This study has a mixed-methods design that includes a one-group pre-post test study and focus group interviews(N=23). From April 16th to June 11th in 2014, total six two-hour sessions of MI training program were provided to the participants. The quantitative outcomes were collected using Global Interpersonal Communication Competence Scale(GICC-15) and Self-efficacy Scale, and the qualitative data were obtained by 5 focus group interviews. Group pre-post changes were evaluated by paired t-tests and the qualitative data were analyzed by content analysis method. Results: MI training program led to significant enhancement in communication skills(Z=-3.62, p<.001) and self-efficacy(Z=-3.67, p<.001). The qualitative study revealed that the participants had positive experiences to express empathy, support self-efficacy, and respect autonomy for their clients applying reflective-listening and affirmation skill. Conclusion: The HVNs who participated in the MI training program showed improved communication skills and self-efficacy in the quantitative and qualitative studies. A randomized clinical trial is needed to confirm the value of MI training program for HVNs.

• Child Health Nursing Research
• /
• v.23 no.4
• /
• pp.429-439
• /
• 2017

Purpose: The aim of this study was to identify the status of psychological health among boys in high school and to examine the mediating effects of social support on the relationship between anger and entrapment on psychological health. Methods: The participants in this study were 193 high school boys from Jeju. Measurements included state-trait anger expression inventory, entrapment scale, student social support scale, and questionnaires to assess mental and physical health. Data were analyzed using independent t-test, one-way ANOVA, $Scheff{\acute{e}}$ test, Pearson correlation coefficient, simple and multiple regression techniques with the SPSS 21.0. Mediation analysis was performed with the Baron and Kenny's method, and Sobel test. Results: Mean scores for anger experience, entrapment, social support, and psychological health were $29.81{\pm}7.34$, $34.09{\pm}16.33$, $45.75{\pm}7.02$, $22.51{\pm}9.91$, respectively. There was a significant correlation between anger experience and psychological health. Entrapment was significantly correlated with psychological health. Social support showed partial mediating effects in the relationship between anger experience and psychological health (Sobel test: Z=54.18. p<.001). Social support showed partial mediating effects in the relationship between entrapment and psychological health (Sobel test: Z=2.24. p=.025). Conclusion: The results indicate a need to develop social support programs for boys in high school.

• The Korean Journal of Rehabilitation Nursing
• /
• v.8 no.1
• /
• pp.59-67
• /
• 2005

Purpose: The purpose of this study is to investigate the effect of Self-Efficacy Promoting Program on Self-Efficacy, Metabolic Control and Self-Care Behaviors in Patients with NIDDM. Method: Data was collected from March 15th to July 15th, 2001. The subjects of the study consisted of 23 NIDDM patients who had visited regularly the endocrinology out-patient department of Gwangju Christian Hospital. The instrument used in the study Paek's self-efficacy measurement scale, was modified by the researcher, self-care behaviors were created by health care teams, and HbA1c for the sugar metabolic control were measured from the patients blood. The Interventions of the self efficacy promoting program were applied 4 hours a week for 6weeks. Data were analyzed with SPSS/PC+, using T-test and Wilcoxon rank sum test. Result: The mean score for self-efficacy was $70.61{\pm}15.48$ of a 140 point scale, the mean score for $HbA_{1c}$ level was $8.07{\pm}1.86%$. The self efficacy promoting program significantly increased the score of self efficacy(Z=-4.198, P=.000). And the self efficacy promoting program was significantly decreased in metabolic control(Z=-2.585, p=.010). Taking medicine and controlling alcohol were the best self care behaviors of this program. Conclusion: It was established that the self efficacy promoting program was effective for improving self efficacy, metabolic level and self care behaviors in patients with NIDDM.

• Journal of the East Asian Society of Dietary Life
• /
• v.15 no.6
• /
• pp.655-662
• /
• 2005

Body content bone mined density and nutrient intake status of 129 college women in Daegu area are analyze4 The mean age was 23.1 years. Bone mineral density was measured in their right heel by SONOST-2000 ultrasound bone densitometer, and nutrient intake was assessed by a Questionnaire. Diet intake data were obtained by using a 24 hours recall method to evaluate the subject's usual diet. The average energy, Ca, Ee, Zn and folate intakes were 64.2, 47.5, 54.7, 62.9 and $57.4\%$ of RDA, respectively. Ca/P and Ca/Protein ratio were 0.46 and 6.7, respectively. The mean adequacy ratio(MAR), an index of overall dietary quality wag 0.6. The index of nutritional quality was under 1.0 for protein(0.7), vitamin A(0.9), E(0.7), $B_1(0.8)$, niacin(0.8), $B_6(0.6)$ and phosphorus(0.6). The less the protein and energy intake, the less the bone mineral density(p<0.05). The intakes of protein(p<0.05) and that of phosphorus(p<0.001) were positively correlated with bone quality index(BQI). The calcium intake was positively correlated with Z-score(p<0.05). The phosphorus intake was positively correlated with T-score(p<0.001) and Z-score(p<0.0001). In conclusion, this study indicates that nutrient intake of the college women is considerably lower than the RDA. Also the BQI is lower than standard.

• Proceedings of the Korean Vacuum Society Conference
• /
• 1995.06a
• /
• pp.154-154
• /
• 1995

The Xu-Tec process is also called the double glow surface alloying technology and is a new method of surface metallurgy which can produce an alloy layers with sp ecial phisical and chemical properties on the surface of common and inexpensive mater ials. Many super alloys and alloy steels, sueh as nickel base alloys, high speed steels and staiinless steels, have been produced by Xu-Tee Process on the surfaces of carbon steels. The depth of the alloy lasyers may vary from several microns up to 300 micr ons with alloying elements in a concentration of few percentage to 100%. World wide patents for Xu-Tec process have been granted in the United states, Canada, United Ki ngdom, Australia and Japan. High performance saw blades have been successfully produced by the Xu-Tee process with much simper processing steps and less cost than bimetal high speed saw blades. A comparison of the cutting times and wear rates of the Xu-Tee blades with the conventional bimetal blades has been made. The Xu-Tee bIases demonstrates sim ilar or better performance than bimetal blades. A Xu-Tec Unit for the commercial pr oduction of Xu-Tec saw blades has been designed and manufactured. This Unit can t reat 10,000 haek saw blades at one time. Three Xu-Tec hack saw blades production I ines have been set up in China. China.

• Investigative Magnetic Resonance Imaging
• /
• v.23 no.1
• /
• pp.38-45
• /
• 2019

Purpose: To demonstrate the high-resolution numerical simulation of the respiration-induced dynamic $B_0$ shift in the head using generalized susceptibility voxel convolution (gSVC). Materials and Methods: Previous dynamic $B_0$ simulation research has been limited to low-resolution numerical models due to the large computational demands of conventional Fourier-based $B_0$ calculation methods. Here, we show that a recently-proposed gSVC method can simulate dynamic $B_0$ maps from a realistic breathing human body model with high spatiotemporal resolution in a time-efficient manner. For a human body model, we used the Extended Cardiac And Torso (XCAT) phantom originally developed for computed tomography. The spatial resolution (voxel size) was kept isotropic and varied from 1 to 10 mm. We calculated $B_0$ maps in the brain of the model at 10 equally spaced points in a respiration cycle and analyzed the spatial gradients of each of them. The results were compared with experimental measurements in the literature. Results: The simulation predicted a maximum temporal variation of the $B_0$ shift in the brain of about 7 Hz at 7T. The magnitudes of the respiration-induced $B_0$ gradient in the x (right/left), y (anterior/posterior), and z (head/feet) directions determined by volumetric linear fitting, were < 0.01 Hz/cm, 0.18 Hz/cm, and 0.26 Hz/cm, respectively. These compared favorably with previous reports. We found that simulation voxel sizes greater than 5 mm can produce unreliable results. Conclusion: We have presented an efficient simulation framework for respiration-induced $B_0$ variation in the head. The method can be used to predict $B_0$ shifts with high spatiotemporal resolution under different breathing conditions and aid in the design of dynamic $B_0$ compensation strategies.