• The Journal of Korean Academy of Prosthodontics
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• v.49 no.3
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• pp.245-253
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• 2011

Purpose: The aim of this in vitro study was to estimate surface characteristic after peptide coating and investigate biological response of human mesenchymal stem cell to anodized titanium discs coated with RGD peptide by physical adhesion and chemical fixation. Materials and methods: Fluorescence isothiocyanate (FITC) modified RGD-peptide was coated on the anodized titanium discs (diameter 12 mm, height 3 mm) using two methods. One was physical adhesion method and the other was chemical fixation method. Physical adhesion was performed by dip and dry procedure, chemical fixation was performed by covalent bond via silanization. In this study, human mesenchymal stem cell was used for experiments. The experiments consisted of surface characteristic evaluation after peptide coating, analysis about cell adhesion, proliferation, differentiation, and mineralization. Obtained data are statistically treated using Kruskal-Wallis test and Bonferroni test was performed as post hoc test (P=.05). Results: The evaluation of FE-SEM images revealed no diffenrence at micro-surfaces between each groups. Total coating dose was higher at physical adhesion experimental group than at chemical fixation experimental group. In cell adhesion and proliferation, RGD peptide coating did not show a statistical significance compared with control group (P>.05). In cell differentiation and mineralization, physical adhesion method displayed significantly increased levels compared with control group and chemical fixation method (P<.05). Conclusion: RGD peptide coating seems to enhance osseointegration by effects on the response of human mesenchymal stem cell. Especially physical adhesion method showed more effective than chemical fixation method on response of human mesenchymal stem cell.

• Journal of Music and Human Behavior
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• v.4 no.2
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• pp.18-40
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• 2007

The purpose of this study was to verify the influence of musical activities on social and emotional behavior of infants, through providing musical activities to the infants who were cared in a nursery and observing the interactions between peer group, or a therapist and an infant derived during them. The subject is 24 infants who are under 2 years of age(25~36months) at two nurseries located in Bundang area, and 13 infants among them are randomly assigned as study group and 11 infants as control group. Pretest and posttest about social and emotional behavior are performed, and ITSEA developed by Brggs-Gowan and Carter(2001) and amended by Shin Ji Yeon(2004) was used as an evaluation tool. Infants' changes of interaction behaviors during musical play were also analyzed quantitatively and qualitatively, and for the analysis, infant's social play behavior examination tool developed by Holloway and Reichhart-Erickson(1988) was adopted. Based on time sampling method, each item of this tool was evaluated. Each session was performed for 15 minutes, and 60 times of analysis about interactions per session was conducted at every 15 seconds. The analysis result was showed with a table and a graph, and described qualitatively about behavior changes. When compared social and emotional positive behavior average figures and negative behavior average figures between study group and control group, this study showed that the positive behavior figure of study group was increased and the negative behavior figure was decreased. While concentration and empathy among positive behaviors increased meaningfully, aggression, defiance, separation anxiety and rejection to new things among negative activities also decreased meaningfully. The conclusion of this study is as follows. First, interactions with peers or a therapist based on music and musical experience make an effect on strengthening positive behavior among social and emotional behavior and decreasing negative behavior. Second, music has influence on negative behaviors more than positive behaviors of an infant, and produces a good effect on sub behaviors of negative behaviors specially.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.1
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• pp.61-69
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• 2009

Statement of problem: Porcelain veneers have become a popular treatment modality for aesthetic anterior prosthesis. Fitting porcelain veneers in the mouth usually involve a try-in appointment, which frequently results in salivary contamination of fitting surfaces. Purpose: An in vitro study was carried out to investigate the effect of silane treatment timing and saliva contamination on the resin bond strength to porcelain veneer surface. Material and methods: Cylindrical test specimens (n=360) and rectangular test specimens (n=5) were prepared for shear bond test and contact angle analysis. Whole cylindrical specimens divided into 20 groups, each of which received a different surface treatment and/or storage condition. The composite resin cement stubs were light-polymerized onto porcelain adherends. The shear bond strengths of cemented stubs were measured after dry storage and thermocycling (3,000 cycles) between 5 and $55^{\circ}C$. The silane and their reactions were chemically monitored by using Fourier Transform Infrared Spectroscopy analysis (FTIR) and contact angle analysis. One-way analysis of variance (ANOVA) and Dunnett's multiple comparison were used to analyze the data. Results: FT-IR analysis showed that salivary contamination and silane treatment timing did not affect the surface interactions of silane. Observed water contact angles were lower on the saliva contaminated porcelain surface and the addition of 37% phosphoric acid for 20 seconds on saliva contaminated porcelain increased the degree of contact angle. Silane applied to the porcelain, a few days before cementation, resulted in increasing the bond strength after thermocycling. Conclusion: Within the limitation of this study, it can be concluded that it would be better to protect porcelain prosthesis before saliva contamination with silane treatment and to clean the contaminated surface by use of phosphoric acid.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.9 no.2
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• pp.1-13
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• 2014

This study is preliminary founding start-ups of restaurant entrepreneurs to study the characteristics of management in order to provide useful information was studied. Survey period is from 2013 March 15 to August 31. About the nature of the preparation and establishment founder findings restaurant entrepreneurs of Western Gyeongnam area were most often in the form of an independent establishment has been compiled, work experience and other industries operating experience was more than restaurant entrepreneurs of operating experience. Hypothesis Testing in accordance with results of this study are as follows. First, the 50 founders than 30 founders quickly when the customer complaint or that service, order food and non-food note is issued after obtaining the order or that provide food, no customer is often inconvenient check the sharing services, such as personnel activities were devoting a lot of effort. Second, the re-startups restaurant entrepreneurs than new startups restaurant entrepreneurs was founded after the founder of career-related customer complaints about food more active coping was, and re-startups restaurant entrepreneurs by the founder other than business founded by the founder of the food-related customer complaints more aggressively for coping, respectively. Third, restaurant entrepreneurs of the store operations management has integrity, words and actions match, such as the degree of belief in the promise of reliability and the possibility of failure, which means the degree of recognition and response efforts are having an impact deal. Fourth, restaurant of food service management services and after-sales service has impact on the founder of the self-efficacy and self-efficacy of pre-service features and reliability founder affecting. Fifth, the revenue of the restaurant for dealing with customer complaints management includes efforts are having an impact. Sixth, restaurant founder of reliability and customer care has influenced the self-efficacy. Seventh, management of operational management activities have a positive impact on business performance are.

• Management & Information Systems Review
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• v.33 no.3
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• pp.167-187
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• 2014

While Korean GAAP had detailed regulations for the measurement and disclosure of operating income in the past, K-IFRS did not provide specific rules for operating income until 2011. Some firms that adopted K-IFRS before 2011 did not disclose or calculated operating income in an inconsistent manner although operating income is usually considered as one of the core information items to assess firm valuation. Inconsistency in firms' treatment of operating income invoked much criticism from diverse users of financial statement. The Korean Accounting Institute (KAI hereafter) revised the K-IFRS rules relevant to operating income in September 2010 in response to the voices raised by the business community, whereby the operating income number is allowed to be calculated in conformity with the previous K-GAAP. This study was motivated by the revision of K-IFRS and aims to provide a clue on the validity of such policy decision. To achieve the research objective, we test the relative value relevance of the alternative operating income numbers under K-IFRS versus K-GAAP. Our main findings are as follows. The value relevance of operating income reported before K-IFRS is proved to be higher than after K-IFRS. K-IFRS operating income adjusted to the previous K-GAAP has greater explanatory power for market values relative to one calculated under the K-IFRS regime. In an additional analysis, the sample was decomposed according to whether the operating income under K-IFRS is greater than under K-GAAP. The difference in the value relevance of K-IFRS versus K-GAAP operating income is significant only in the subsample consisting of firms which reports higher operating income under K-IFRS compared to K-GAAP. Also, the firms which would have reported negative operating income on a consecutive basis are more likely to have chosen K-IFRS, resulting in higher numbers than otherwise. It is likely that firms facing the threat of delisting due to consecutive operating loss reporting are more likely to have adopted K-IFRS disclosure rules by which they could report higher operating income numbers. To sum up, these results corroborate the limitation inherent in the K-IFRS regarding operating income disclosures. This paper suggests that the recent revision of K-IFRS implemented by KAI is likely to mitigate some of afore-mentioned limitations effectively.

• Journal of the Korean Society of Earth Science Education
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• v.3 no.2
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• pp.99-108
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• 2010

This study lays its purpose on examining the effects of lessons with the application of drawing tasks on changes in conception among gifted science students. The lesson with the application of drawing tasks means the lesson where students express key concepts regarding lesson subjects in drawings which are then applied to the lessons to develop conception among the learners. This study analyzed the effectiveness of lessons by comparing conception scores before and after experiments between an experiment group with the application of drawing tasks and a control group with normal lessons for the gifted in general for 8 months from March to October, 2008. In addition, the researcher examined how the effectiveness of the developed lessons show differently according to levels of meta-cognition, creative problem-solving abilities, and scientific inquiry skills among the gifted students. The results from this study are as the following. First, lessons with the application of drawing tasks were effective in changing conception among the gifted science students. It is possibly because in the process where one student compare his/her own drawings with the others' ones and discuss them, changes in conception occurred effectively among the learners. Second, it was revealed that lessons utilizing drawing tasks have equal effects on changes in conception among both student groups irrespective of their levels of meta-cognition. Accordingly the lesson for changing perceptions utilizing drawing tasks developed in this study is a program which can be applied to all gifted science students in order to change conception among them. Third, lessons utilizing drawing tasks have the greatest effects on the gifted science students at a 'middle' level of creative problem solving abilities. Fourth, lessons utilizing drawing tasks have the greatest effects on the gifted science students at a 'middle' level of scientific inquiry skills. Putting these results together, it is thought that if lessons utilizing drawing tasks are applied to gifted science students, not only their concepts would be changed effectively but also their attitudes toward science would be changed positively.

• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.1
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• pp.90-93
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• 2010

Purpose: In our nuclear medicine department, we suggested AMC RBC labeling method improved by modifying a part of existing modified in-vitro method to raise the efficiency of $^{99m}Tc$-RBC labeling. However, it needs to be more additional time and efforts than existing modified in-vitro method because the AMC RBC labeling method has to carry out the centrifugal separation process for 3~5 minutes. Therefore, in this study, we conducted researches to aim to maintain stable labeling effects and supplement a problem about additional time by reducing rotating time when labeling $^{99m}Tc$-RBC. Materials and Methods: This research has been conducted the object of 30 patients who examined study using $^{99m}Tc$-RBC and agreed to this research at our hospital from May 2009 to September 2009. We made 4 blood samples which consisted of ACD 1 cc along with 5 cc blood from each patient and used the AMC RBC labeling method. At this moment, each labeling efficiency was calculated by different rotating time 5 min, 10 min, 15 min, and 20 min and then we compared differences. Results: As a result, When comparing the $^{99m}Tc$-RBC labeling method efficiency by using the AMC RBC labeling method which differents from rotating time, each labeling efficiency were $92.3{\pm}5.0%$ in 5 min, $95.9{\pm}5.0%$ in 10 min, $97.4{\pm}4.9%$ in 15 min and $97.7{\pm}4.8%$ in 20 min. We analyzed differences of the labeling efficiency from change of rotating time by using an one-way ANOVA and verified that in Duncan method. There was relatively efficiency low in 5min rotating time and no statistically significant change in over. Conclusions: When comparing a existing method, the AMC RBC labeling method which goes through the centrifugal separation process again offers more favorable condition to combine RBC with $^{99m}TcO4^-$ by eliminating an plasma ingredient. When using the modified in-vitro method, we have almost 20 min to rotate to acquire stable labeling efficiency. But, when using the AMC RBC labeling method, we acquire labeling efficiency well what we want within only 10 min to rotate. Decrease of rotating time can complement the AMC RBC labeling method which goes through the centrifugal separation process again and also provide more rapid study such as G-I bleeding study due to fast labeling.

• Journal of Plant Biotechnology
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• v.40 no.1
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• pp.18-26
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• 2013

Genetically modified (GM) rice Agb0101, which expresses the insecticidal toxin modified cry1Ac (mcry1Ac1) gene, was developed by the Rural Development Administration in Korea. To monitor the probable release of Agb0101 in the future, it is necessary to develop a reliable detection method. Here, we developed the PCR detection method for monitoring and tracing of GM rice. The primer pair (RBEgh-1/-2) from a starch branching enzyme (RBE4) gene was designed as an endogenous reference, giving rise to an expected PCR amplicon of 101 bp. For the qualitative PCR detection, construct- and event-specific primers were designed on the basis of integration sequence of T-DNA. Event-specific PCRs amplified specifically 5'- or 3'-junction region spanning the native genome DNA and the integrated gene construct, while none of amplified product was shown on crops, rice varieties, and other insect-resistant transgenic rice lines. The event-specific real-time PCR method was performed using TaqMan probe and plasmid pRBECrR containing both rice endogenous gene RBE4 sequence and 5'-junction sequence as the reference molecule. The absolute limit of quantification (LOQ) of real-time PCR was established with around 10 copies for one plasmid molecule pRBECrR. Thereafter, the different amounts of transgenic rice (1, 3, 5, and 10%, respectively) were quantified by using the established real-time PCR method, with a range below 19.55% of the accuracy expressed as bias, 0.06-0.40 of standard deviation (SD) and 3.80-7.01% of relative standard deviations (RSD), respectively. These results indicate that the qualitative and quantitative PCR methods could be used effectively to detect the event Agb0101 in monitoring and traceability.

• Journal of Dental Rehabilitation and Applied Science
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• v.24 no.3
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• pp.231-242
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• 2008

Purpose: The purpose of this study was to investigate the bond strength of the core-veneer interface in all ceramic systems. Material and Methods: The all ceramic systems tested with their respective veneer were IPS Empress 2 with IPS Eris, IPS e.max Press with IPS e.max Ceram and IPS-e.max ZirCAD with IPS e.max Ceram. Cores (N=36, N=12/group, diameter: 10mm, thickness: 3mm) were fabricated according to the manufacturer's instruction and cleaned with ultrasonic cleaner. The veneer(diameter: 3mm, thickness: 2mm) were condensed in stainless steel mold and fired on to the core materials. After firing, they were again ultrasonically cleaned and embedded in acrylic resin. The specimens were stored in distilled water at $37^{\circ}C$ for 1 week. The specimens were placed in a mounting jig and subjected to shear force in a universal testing machine(Z020, Zwick, Germany). Load was applied at close to the core-veneer interface as possible with crosshead speed of 1.00mm/min until failure. Average shear bond strengths(MPa) were analyzed with a one-way analysis of variance and the Tukey test(${\alpha}=.05$). The failed specimens were examinated by scanning electron microscopy(JSM-6360, JEOL, Japan). The pattern of failure was classified as cohesive in core, cohesive in veneer, mixed or adhesive. Results: The mean shear bond strength($MPa{\pm}SD$) were IPS e.max Press $32.85{\pm}6.75MPa$, IPS Empress 2 $29.30{\pm}6.51MPa$, IPS e.max ZirCAD $28.10{\pm}4.28MPa$. IPS Empress 2, IPS e.max Press, IPS e.max ZirCAD were not significantly different from each others. Scanning electron microscopy examination revealed that adhesive failure did not occur in any all ceramic systems. IPS Empress 2 and IPS e.max Press exhibited cohesive failure in both the core and the veneer. IPS e.max ZirCAD exhibited cohesive failure in veneer and mixed failure.

• Korean Journal of Cognitive Science
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• v.19 no.4
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• pp.331-367
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• 2008

This study aims to validate a web-based neuropsychological testing tool developed by Kwak(2007) and to suggest solutions to potential problems that can deteriorate its validity. When it targets a wider range of subjects, a web-based neuropsychological testing tool is challenged by high drop-out rates, lack of motivation, lack of interactivity with the experimenter, fear of computer, etc. As a possible solution to these threats, this study aims to redesign the user interface of a web-based attention testing tool through three phases of study. In Study 1, an extensive analysis of Kwak's(2007) attention testing tool was conducted to identify potential usability problems. The Heuristic Walkthrough(HW) method was used by three usability experts to review various design features. As a result, many problems were found throughout the tool. The findings concluded that the design of instructions, user information survey forms, task screen, results screen, etc. did not conform to the needs of users and their tasks. In Study 2, 11 guidelines for the design of web-based attention testing tools were established based on the findings from Study 1. The guidelines were used to optimize the design and organization of the tool so that it fits to the user and task needs. The resulting new design alternative was then implemented as a working prototype using the JAVA programming language. In Study 3, a comparative study was conducted to demonstrate the excellence of the new design of attention testing tool(named graphic style tool) over the existing design(named text style tool). A total of 60 subjects participated in user testing sessions where their error frequency, error patterns, and subjective satisfaction were measured through performance observation and questionnaires. Through the task performance measurement, a number of user errors in various types were observed in the existing text style tool. The questionnaire results were also in support of the new graphic style tool, users rated the new graphic style tool higher than the existing text style tool in terms of overall satisfaction, screen design, terms and system information, ease of learning, and system performance.