• The Journal of Korean Academy of Prosthodontics
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• v.50 no.2
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• pp.112-118
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• 2012

Purpose: The purpose of this study was to evaluate the difference in shear bonding strength between resin cements to dental materials when a universal primer (Monobond plus) was applied in place of a conventional primer. Materials and methods: Four groups of testing materials: gold alloy (Argedent Euro, n = 16), non precious metal (T-4, n = 20), zirconia (Cercon, n = 20) and glass ceramic (IPS e.max press, n = 20), were fabricated into discs, which were embedded in an acrylic resin matrix. The gold alloy specimens were airborne-particle abraded, 8 of the specimens were coated with Metal primer II, while the remaining 8 specimens were coated with Monobond plus. The non precious and zirconia specimen were airborne-particle abraded then, the control group received Alloy primer coating, while the other was coated with Monobond plus. Glass ceramic specimens were etched. 10 specimens were coated with Monobond-S and the remaining specimens were coated using Monobond plus. On top of the surface, Multilink N was polymerized in a disc shape. All of the specimens were thermal cycled before the shear bonding strength was measured. Statistical analysis was done with Two sample $t$-test or Mann-Whitney U test (${\alpha}$=.05). Results: There were no significant differences in bonding strength depending on the type of primer used in the gold alloy and glass ceramic groups ($P$>.05), however, the bonding strengths of resin cements to non precious metal and zirconia groups, were significantly higher when the alloy primer was used ($P$<.05). Conclusion: Within the limitations of this study, improvement of universal primers which can be applied to all types of restorations is recommended to precious metals and zirconia ceramics. But, the bond strengths of non precious metals and zirconia ceramics were significantly lower when compared to a 10-MDP primer. More research is needed to apply universal primers to all types of restorations.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.2
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• pp.190-201
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• 2004

The aim of this study was to evaluate the resistance to degradation and to compare the wear resistance characteristics of four esthetic restorative materials in an alkaline solution. The brands studied were Charmfil, Charmfil flow(composite resin), Compoglass F and PrimaFlow(compomer). The results were as follows: 1. The mass loss were not significantly different among the materials(p>0.05). 2. The sequence of the degree of degradation layer depth was in descending order by Compoglass F, PrimaFlow, Charmfil, and Charmfil flow. There were significant differences between Compoglass F and the others(p<0.05). 3. The sequence of the Si loss was in descending order by Charmfil flow, Charmfil, PrimaFlow, and Compoglass F. There were significant differences among these materials(p<0.05). 4. When observed with SEM, destruction of bonding between matrix and filler was observed and when observed with CLSM, the depth of degradation layer of specimen surface was observed. 5. The sequence of maximum wear depth was in descending order by Comfoglass, PrimaFlow Charmal, and Charmfil flow. There were significant differences among these materials(p<0.05). 6. The correlation coefficient between Si loss and degradation layer depth (r=0.602, p<0.05) Vicker's hardness number and maximum wear depth (r=0.501, p<0.05) were relatively high. These results indicate that wear and hydrolytic degradation may be considered to be evaluation factors of composite resins and compomers.

• Journal of Radiation Protection and Research
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• v.23 no.3
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• pp.123-138
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• 1998

Characteristics of element responses of Panasonic UD802 personnel dosimeters in the X, ${\beta}$, ${\gamma}$, ${\gamma}/X$, ${\gamma}/{\beta}$ and ${\gamma}$/neutron mixed fields were assessed. A dose-response algorithm has been developed to decide the high probability of a radiation type and energy by using the distribution in all six ratios of the multi-element TLD. To calculate the 4-element response factors and ratios between the elements of the Panasonic TLDs in the X, $\beta$, and $\gamma$ radiation fields, Panasonic’s UD802 TLDs were irradiated with KINS’s reference irradiation facility. In the photon radiation field, this study confirms that element-3 (E3) and element-4 (E4) of the Panasonic TLDs show energy dependent both in low- and intermediate-energy range, while element-1 (E1) and element-2 (E2) show little energy dependency in the entire whole range. The algorithm, which was developed in this study, was applied to the Panasonic personnel dosimetry system with UD716AGL reader and UD802 TLDs. Performance tests of the algorithm developed was conducted according to the standards and criteria recommended in the ANSI N13.11. The sum of biases and standard deviations was less than 0.232. The values of biases and standard deviations are distributed within a triangle of a lateral value of 0.3 in the ordinate and abscissa, With the above algorithm, Panasonic TLDs satisfactorily perform optimum dose assessment even under an abnormal response of the TLD elements to the energy imparted. This algorithm can be applied to a more rigorous dose assessment by distinguishing an unexpected dose from the planned dose for the most practical purposes, and is useful in conducting an effective personnel dose control program.

• Journal of The Korean Association For Science Education
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• v.24 no.5
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• pp.902-915
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• 2004

Science drama can be an useful tool for understanding the nature of science, Science-Technology-Society relationship by providing indirect experiences to young students. Specific science concept and knowledge can also be learned with high interests. In this study, to explore the usefulness of science drama in elementary science lessons, two scripts of science drama and lesson plans were developed and implemented. Six step model for science drama lessons was also suggested. One was 'Manhattan Project' which dealt with social, ethical responsibility in using science & technology (science argument drama), and the other was 'Mom, My blood type is O' which explained the heredity of blood type (science concept drama). Two teachers were asked to write their journals during preparation and implementation of science drama lessons, and the lessons were observed by the researcher and video taped for analysis. Some students were interviewed just after the lessons by the teacher and all students were asked to write their impressions, change of their thought, what is leant etc. Overall responses of students and teachers on the two science drama lessons were very positive, 'Mom, My blood type is O' got more positive responses, and girls were more positive than boys. Some students anticipated another science drama even suggest topics for it. 'Mom, My blood type is O' was successful in making students (grade 3) understand the knowledge related with heredity of blood type (71% of the students got perfect answer). In 'Manhattan Project' students (grade 5) perceived more diverse location of responsibility after the lesson, but the danger and harmfulness of atomic power was embossed. This implied the need of more careful planning for the relevant learning activities before and after the play of science drama.Two teachers perceived the science drama as a new, useful tool for some subject which is hard to deal with by other teaching method. They were also satisfied with students' high interest and engagement during the science drama lessons but the extra time and effort for the lessons were pointed out as a main difficulties.

• Journal of The Korean Association For Science Education
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• v.35 no.2
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• pp.247-258
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• 2015

Students are engaged in classroom learning, and classroom learning occurs not only through conversation but also through nonverbal behavior. In science classrooms especially, there are meaningful nonverbal behaviors such as practical activities like observation and measurement. But these behaviors have not been properly investigated by existing instruments that try to measure students' engagement. This study aims to develop a new instrument for analyzing students' behavioral engagement especially in science classrooms. The method of developing the instrument was structured along three steps. First, student behaviors have been classified into fourteen categories through literature review and a series of observation of elementary science classroom. Second, based on these, a framework for analyzing student behavioral engagement has been developed. With the framework, every student moment could be labeled as Participatory Speech or Participatory Silence or Non-Participatory Speech or Non-Participatory Silence. Third, an instrument to which the framework is applied has been developed by using Microsoft Excel. As a trial, two fourth-grade students in elementary science class were analyzed with this instrument. The results of the trial analysis shows that the longest period of a science lesson was occupied by Participatory Silence (63% and 72%). Among the participatory silence, 'listening' was the most common (51% and 42% of the trial lesson) and 'observing' which is a specific behavior to science was the fourth position (17% and 17% of the trial lesson). It is expected that the developed instrument could be used in improving our understanding of the patterns of student engagement in science classrooms.

• Journal of Aquaculture
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• v.20 no.1
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• pp.19-25
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• 2007

For establishing a basal diet for the Pacific bluefin tuna Thunnus orientalis (PBT), feeding stimulants were initially identified by omission test using the synthetic extract of horse mackerel, Trachurus japonicus. Four feeding trials were conducted using juvenile PBT weighing $9.0{\pm}0.91\;g$ (trial 1, 2 and 3) and $1.6{\pm}0.23\;g$ (trial 4), which were originated from an artificial seedling production. The fish fed the casein diet with each test solution were added at the ratio of 100 g casein diet to 100 g jack mackerel muscle. A complete synthetic extract of jack mackerel containing all 3 fractions, amino acid, nucleotide and organic nitrogenous base, exhibited a comparable feeding stimulant activity compared to that of natural extract. The omission of nucleotide or amino acid fraction showed lower feeding activity, but the omission of other nitrogenous fraction maintained a similar feeding stimulant activity compared to that of the synthetic extract (trial 1). Inosine-5' monophosphate $Na_2$ (IMP) was identified as a major constituent for maintaining feeding activity. The mixture of L-alanine, L-glutamic acid, L-histidine, L-lysine, taurine and IMP induced a similar feeding activity compared to that of the synthetic extract (trial 2 and 3). In trial 4, the highest feeding activity was finally obtained in the mixture of L-histidine, L-glutamine and IMP, followed by the synthetic extract, the mixture of L-lysine, L-alanine and IMP, IMP and the mixture of L-histidine, L-glutamic acid, L-lysine and L-alanine. These results revealed that the mixture of L-histidine, L-glutamic acid and IMP for the proper feeding stimulant of PBT in this study.

• Culinary science and hospitality research
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• v.18 no.4
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• pp.243-254
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• 2012

The purpose of this study is to rapidly produce a sauce using paprika powder in a short period. The test results of moisture content, pH, salinity, color, texture, reducing sugar, amino-nitrogen, and sensory testing are as follows. The water content of sauce (CON) using paprika powder was 26.31%, whereas 31.58% in SP1, 31.40% in SP2, 30.84% in SP3, and 24.08% in SP4. pH value increased with increasing paprika powder (P<0.001). Salinity ranged from 4.87% to 5.22%, which showed a lower value than that of a former study. In terms of color, SP3 showed the highest L value (28.01), and CON showed the highest a and b values (P<0.001). In textural properties, CON showed the highest hardness of 205.50, whereas SP3 showed the lowest hardness of 106.53. Contrary to the results for hardenss (ED:?) CON showed the lowest adhesiveness which was -704.17, SP3 showed the highest value which was -348.93. SP1, and SP2 showed the highest reducing sugar value (P<0.001), and SP1 and SP4 showed the highest and lowest values of amino-nitrogen, respectively (P<0.001). In the results of sensory tesating, SP2 showed the greatest appearance and flavor, but was not found to be significantly different to any of the others. CON, SP1 and SP2 showed the best texture(P<0.05) and SP2 showed the best interest among them with no significant difference. According to these results, SP2 made with 200g of paprika powder, 150g of soy powder, 600g of grain syrup, 500g of water, and 75g of salt showed the highest sensory interest value and was determined to be the most suitable for making the paprika sauce.

• Child Health Nursing Research
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• v.19 no.2
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• pp.85-93
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• 2013

Purpose: The study purposes were to describe the process of developing the Korean versions of the Six Dimension Scale of Nursing Performance (Six-D) and Student Nurse Stress Index (SNSI) and psychometric evaluation of the two measurements. Methods: This was a methodology study using a descriptive cross-sectional design with 51 nursing students in 4th year of university. Internal consistency reliability was assessed using Cronbach alphas. Construct validity was determined by exploring correlations among Six-D, SNSI, objective structured clinical examination (OSCE), self-efficacy and grade point average (GPA). Results: Internal consistency reliability of Six-D and SNSI was acceptable with Cronbach's ${\alpha}$ of .95 and .82. Correlation analysis to determine construct validity revealed that Six-D presented positive correlations with OSCE (r=.109~.272) and self-efficacy (r=.005~.161) and negative correlation with GPA (r=-.246~-.394), although all were not statistically significant. SNSI presented all negative correlations with OSCE (r= -.007~-.238), self-efficacy (r=-.246~-.394), and GPA (r=-.092~-.426) and were mostly statistically significant except OSCE. Conclusion: Six-D needs more evidence to confirm validity to predict observed clinical competency and theoretical relationships with self-efficacy and GPA. However, SNSI presented trends of expected relationships with relevant variables. Therefore, further research is recommended in testing validity of Six-D with other student populations.

• Journal of Dental Rehabilitation and Applied Science
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• v.30 no.2
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• pp.121-130
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• 2014

Purpose: To assess the surface profile of dentinal wall, dentin chips and smear layer during the canal shaping with rotary (ProTaper) and ProFile and reciprocating (WaveOne) nickel-titanium file. Materials and Methods: Sixty human extracted mandibular premolars and incisors with single canals were randomly selected. Three experimental groups (n = 20) were instrumented with ProTaper (F2), ProFile (25/.06), WaveOne (25/.08) with irrigation of 2.5% NaOCl. The dentin chips were collected from flute of file during each canal preparation. After canal preparation, roots were grinded and each group was divided into two subgroups (n = 10) for surface profile and smear layer of dentinal wall of shaped root canal. Each specimen was observed under scanning electron microscope for evaluating size of dentin chips, root canal surface recessions and smear layer. Scores of Smear layer were statistically analyzed using Kruskal Wallis test and Mann Whitney test at P = 0.05 level. Results: The size of dentin chips from ProFile, ProTaper and WaveOne was up to $7{\mu}m$, $6.5{\mu}m$, and$4{\mu}m$, respectively. In the surface profile, the width of surface irregularity was measured and Profile, ProTaper and WaveOne was up to $150{\mu}m$, $70{\mu}m$, and $80{\mu}m$, respectively. Completely cleaned root canals were not found. In the middle and apical third of the canals, WaveOne group showed higher smear layer score than ProFile and ProTaper groups (P < 0.05). Conclusion: Within limits of this study, reciprocating motion WaveOne group was not significant difference of shaping ability with the full-sequence ProFile and ProTaper systems except canal clearness of middle and apical third of root canal. When using WaveOne to shaping root canal, thorough root canal irrigation is recommended.

• Tuberculosis and Respiratory Diseases
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• v.53 no.2
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• pp.136-147
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• 2002

Background : Interstitial lung disease has various manifestations that are differentiated by their pathology, progress and treatment. However, all manifestations eventually progresses to pulmonary fibrosis. Recent studies have shown that apoptosis of pulmonary epithelial cells might be related to pulmonary fibrosis. The correlation of the apoptotic index with the clinical manifestations, pathological findings, HRCT findings and the response to treatment were examined. Materials and Methods : Twenty subjects (14 men, 16 women), who had been diagnosed with interstitial lung disease through an open lung biopsy, were enrolled in this study. The subtypes were one AIP, two NIP, eight BOOP, and seven UIP cases. The apoptotic index was scaled from 0-2 depending on the fraction of positive staining cells by TUNEL method. The clinical severity was assessed by a modification of a previously developed CRP scoring system. The pathologic scores were based on 4 components: fibrosis, cellularity, desquamation, and granulation. In the HRCT study, each lobe was scored by the radiologists on a scale for both fibrosis and ground-glass attenuation. The treatment response was assessed by an increase in more than 10% of the CRP score, and comparing the results 3 months before and after treatment. Results : The apoptotic index showed no correlation with the CRP and HRCT scoring system. The apoptotic index correlated with the pathologic elements including fibrosis, cellularity and the desquamation score (p<0.05). Of the 16 patients who received corticosteroid therapy, 9 patients (56.3%) responded to therapy. There was no correlation between the response to corticosteroid and the apoptotic index. In the case of patients with acute and subacute ILD, the apoptotic index showed a correlation with the cellularity, desquamation, and the total histological score (p<0.05). In the case of patients with chronic ILD, the apoptotic index correlated with the fibrosis and cellularity score (p<0.05). Conclusion : Apoptosis of the pulmonary epithelial cells is implicated in the pathogenesis of interstitial lung disease particularly on a pathological basis.