• The Journal of Korean Academy of Prosthodontics
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• v.49 no.4
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• pp.324-332
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• 2011

Purpose: The purpose of this study was to compare the stress distribution of teeth and jaw on load by differentiating property of materials according to each layer of widely used mouthguard. Materials and methods: A Korean adult having normal cranium and mandible was selected to examine. A customized mouthguard was constructed by use of DRUFOMAT plate and DRUFOMAT-TE/-SQ of Dreve Co. according to Signature Mouthguard system. The cranium was scanned by means of computed tomography with 1mm interval. It was modeled with CANTIBio BIONIX/Body Builder program and simulated and interpreted using Alter HyperMesh program. The mouthguard was classified as follows according to the layers. (1) soft guard (Bioplast)(SG) (2) hard guard (Duran)(HG) (3) medium guard (Drufomat)(MG) (4) soft layer + hard layer (SG + HG) (5) hard layer + soft layer (HG + SG) (6) soft layer + hard layer + soft layer (SG + HG + SG) (7) hard layer + soft layer + hard layer (HG + SG + HG) The impact locations on mandible were gnathion, the center of inferior border, and the anterior edge of gonial angle. And the impact directions were oblique ($45^{\circ}$). The impact load was 800 N for 0.1 sec. The stress distribution was measured at maxillary teeth, TMJ and maxilla. The statistics were conducted using Repeated ANOVA and in case of difference, Duncan test was used as post analysis. Results: In teeth and maxilla, the mouthguard contacting soft layer of mandibular teeth presented lowest stress measure and, in contrast, in condyle, the mouthguard contacting hard layer of mandibular teeth presented lowest stress measure. Conclusion: For all impact directions, soft layer + hard layer + soft layer, the mouthguard with three layers which the hard layer is sandwiched between two soft layers, showed relatively even distribution of stress in impact.

• Journal of Life Science
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• v.26 no.6
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• pp.633-639
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• 2016

Biomaterials including polymer, metal, ceramic, and composite have been widely applied for medical uses as medical fibers, artificial blood vessels, artificial joints, implants, soft tissue, and plastic surgery materials owing to their physicochemical properties. However, the biocompatibility and toxicity for film- and plate-form biomaterials is difficult to measure in mammalian cells because there is no appropriate incubation system. To solve these problems, we developed a novel mammalian cell culture system consisting of a silicone ring, top panel, and bottom panel and we applied two polymer films (PF) and one metal plate (MP). This system was based on the principal of sandwiching a test sample between the top panel and the bottom panel. Following the assembly of the culture system, SK-MEL-2 cells were seeded onto Styela Clava Tunic (SCT)-PF, NaHCO₃-added SCT (SCTN)-PF, and magnesium MP (MMP) and incubated at 37℃ for 24 hr and 48 hr. An MTT assay revealed that cell viability was maintained at a normal level in the SCT-PF culture group at 24 or 48 hr, although it rapidly decreased in the SCTN-PF culture group at 48 hr. Furthermore, the cell viability in the MMP culture group was very similar to that of the control group after incubation for 24 hr and 48 hr. Together, these results suggest the sandwich-type mammalian culture system developed here has the potential for the evaluation of the biocompatibility and toxicity of cells against PF- and MP-form biomaterials.

• Communications of Mathematical Education
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• v.23 no.1
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• pp.1-38
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• 2009

This study investigates the relationships of perfectionism and the affective traits(academic self-concept, learning attitude, interest, mathematical anxiety, learning habits) in mathematics between the gifted students and the regular students in Korean Middle Schools. The findings of this study can be used for the understanding of the gifted students, and as data or resources for counsellors when they advise the gifted students on enhancing study strategies and developing future courses. This study was investigated by measuring the relationships between perfectionism and the affective traits on mathematics between two groups. Here, the correlation analysis, t-test, and regression analysis of the SPSS for Window 12.0 Program were applied to measure the differences of both groups. Therefore, there were no differences in perfectionism between the gifted students and the regular students. But the self-oriented perfectionism of the gifted students appeared higher compare with regular students. The affective traits in mathematics of the gifted students appeared more positive compare with regular students. There were a few correlations between the perfectionism and the affective traits in mathematics at two group all. however the self-oriented perfectionism and the affective traits in mathematics showed to correlation. There were several suggestions based on the results of this study. First, the results showed that professional assistance is needed for the gifted students so that their perfectionism flows positively into developing their gifts. Secondly, the results suggested that specialized mathematical program reflecting on the affective traits of the gifted students in mathematics should be offered.Lastly, tthe results of this study suggested a researcher regarding relevance with perfectionism and affective traits regarding subject shall be performed more. The result of research shall be included to contents of training for the gifted students and their parents.

• Journal of Physiology & Pathology in Korean Medicine
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• v.26 no.6
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• pp.908-914
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• 2012

To investigate the difference and change of ingredient and efficacy of Galgeun-tang (GGT) according to extraction solvent, water and 70% EtOH, the quantities of index components and the several in vitro activities of two kinds of GGT extract were compared. The contents of extracts were analyzed with HPLC. The biological activities such as anti-inflammatory and anti-obesity effects were measured through cell line-based in vitro assay. The cytotoxicity was measured by CCK-8 assay in RAW 264.7 cell, BEAS-2B cell, HaCaT cell and 3T3-L1 cell. We compared effects of two kinds of extract by measuring NO, PGE2, IL-6 and TNF-${\alpha}$ in RAW264.7 cell, RANTES in BEAS-2B cell, MDC and RANTES in HaCaT cell and GPDH activity and leptin level in differentiated 3T3-L1. 70% EtOH extract of GGT contained more compositions than water extract. The inhibitory effect of water extract of GGT on NO in RAW 264.7 cell and GPDH activity in 3T3-L1 was stronger than that of 70% EtOH. 70% EtOH has a stronger inhibitory effect on PGE2 in RAW264.7 cell, RANTES in BEAS-2B cell, MDC, RANTES in HaCaT cell, leptin in 3T3-L1 cell than water extraction. These results suggest that the ingredient and efficacy from 70% EtOH extract of GGT are more effective than water extract.

• Journal of Sensor Science and Technology
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• v.2 no.1
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• pp.101-108
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• 1993

$TiO_{2}$/Se : Te heterojunction for color sensor has been fabricated by RF reactive sputtering and thermal evaporation methods onto glass substrate. The optimum deposition condition of $TiO_{2}$ films was such that RF power was 120 W, substrate temperature was $100^{\circ}C$, oxygen concentration was 50%, working pressure was 50 mTorr for the $TiO_{2}$ film thickness of $1000{\AA}$. In this case, the optical transmittance of $TiO_{2}$ film at 550 nm-wavelength was 85%, resistivity was $2{\times}10^9{\Omega}{\cdot}cm$, refractive index was 2.3, and optical bandgap was 3.58 eV. The composition ratio of 0 to Ti by AES analysis was 1.7. When $TiO_{2}$ films were annealed at $400^{\circ}C$ for 30 min. in $O_{2}$ ambient, the optical transmittance of $TiO_{2}$ films at the wavelength range of $300{\sim}580$ nm was improved from 0 to 25%. When Se : Te films were annealed at $190^{\circ}C$ for 1 min., photosensitivity under illumination of 1000 lux was 0.75. The optical bandgap of Se : Te films was 1.7 eV. The structures of Se : Te films were the hexagonal with (100) and (110) orientation. The spectral response of a-Se was improved by the addition of Te, especially in the long wavelength region. The $TiO_{2}$/Se : Te heterojunction showed wide spectral response, and more improved one than that of a-Si film in the blue light region.

• Development and Reproduction
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• v.8 no.2
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• pp.119-122
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• 2004

It is well known that unidentified factors in sera, hormones and growth factors promote the proliferation of granulosa cells and nuclear maturation of bovine COCs in vitro. Attemps had been developed the simple composition of culture media and similar system to in vivo conditions has been applied. In the present study, we investigated the effect of TGF-${\beta}$ on in vitro maturation and in vitro development of Hanwoo COCs. When the COCs were matured in TCM 199 containing 0.1, 1 or 10 ng/ml TGF-${\beta}$ for 24 hrs, metaphaseⅡ of COCs were obtained 95.8%, 100% of matured COCs, respectively and there were no differences among the concentrations of TGF-${\beta}$. Matured COCs with TGF-${\beta}$ cultured in maturation medium after in vitro fertilization, developmental rate to blastocyst were 0~0.8%. Matured COCs with TGF-${\beta}$ were cultured in TCM 199+10% FBS, 0.8% BSA, 0.1% PVA, blastocyst formation were showed in 12.4%, 12.8%, 8.5% of those and cultured in IVMD or IVD without serum were 38.4%, 34.8%, respectively. There were significant differences among the media (P<0.05). TGF-${\beta}$ is available for i vitro maturation of bovine COCs, but further investigation would be need for finding the synergistic autocrine/paracrine fashion of other growth factors in early bovine development.

• Archives of design research
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• v.18 no.3 s.61
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• pp.129-138
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• 2005

It has been assumed that the clarification of a message is a necessary element for successful communication. However, in the today's complicated and changing environment of business marketing media, it is shown that the clarification of the message of advertisement may inhibit the effectiveness of communication. This study was to examine what was effective communication in advertisement when the company, provoking the people's negative emotional response, needs to establish new identities such as the goals and the special fields of business. In particular, the study was to investigate what effect the advertising strategy of strategically emitting ambiguous messages makes on the consumer's recognition, emotional attitude, reliability, and attitude towards the company. It was hypothesized that an ambiguous message in an advertisement has an effect on the consumer's recognition, emotional attitude, reliability, and attitude towards the company. Three texts from the 'Imagination Praises' campaign of KT&G which has been in process since 2003 were systematically sampled and the survey was performed by the means of questionnaires made on the sample The results showed that the ambiguous message of advertising texts gained better responses on the consumer's attention, good impression, affirmation, memory, sympathy than the dear message and that the ambiguous message had an effect on the consumer's attitude towards the advertisement itself. Thus, it could be tentatively concluded that the ambiguous message could be more effective in recognition and recall to promote the changes of identities of the company having the people's unfavorable emotion. But there wasn't any evidence that an ambiguous message in an advertisement was more effective in terms of the consumer's emotional response, reliability, and attitude towards the company. From this, it could be inferred that the receiver had an uncomfortable, doubtful and negative attitude about the implicit expressive code contained in the message. In the future deeper qualitative studies can compensate for the limited explanation of this empirical study focused on statistical analyses.

• 대한공업교육학회지
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• v.45 no.1
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• pp.63-83
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• 2020

The purpose of this study is to provide the basic materials needed to plan the NCS Learning Module to be used effectively in practical courses. In this study, teachers and students' satisfaction surveys were collected about the NCS (National Competency Standards) learning module, career and field practice, practical environment used in the construction subject course. This study was conducted on public high schools in Chungcheong province (including Daejeon), which is operating practice course using the NCS learning module. The research questions are as follows; First, how was the satisfaction of teachers and students in the practical subject class using NCS learning module? Second, what is the degree of satisfaction of teacher's career and field practice guidance, student's career decision and field practice after the practical course using NCS learning module? Third, the satisfaction level of the developed NCS learning module and practical subject class using the same was determined by setting whether the number of training of NCS-related teachers or the presence or absence of on-the-job training of students were affected? The results of the study are as follows; As a result of comparing the teachers' and students' satisfaction, the students showed satisfaction in all items, whereas the teachers showed 'content level', 'interest', 'necessary knowledge', 'skill acquisition', 'Improvement of practical skills (level of skill performance)', 'scale of experimental practice', and 'items of experimental practice equipment' were dissatisfied. It was found that the number of NCS related teachers' training (or absence) or the presence of students on the field had an effect on the satisfaction of the developed NCS learning module and the practical course using it. In order to fully utilize the developed NCS learning module in the practical course, it is required to develop and construct the teaching material of the teacher who can serve as an intermediary for conceptualization and understanding of job skills. It is necessary to increase the number of education and training specialists to positively reflect the demands of the education field.

• Journal of Veterinary Clinics
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• v.10 no.1
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• pp.65-94
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• 1993

This study examined metabolic profiles of 1349 Holstein cows from 91 commercial herds. Thirteen parameters which are consisted of twelve blood components and body condition score were examined and their mean values. standard deviations and standard limits, which are 80% confidential limits, in each lactational stage were reported. The variations of each parameter affected by season, individual milk yield, adjusted corrected milk yield of herd. and lactation number were also reported. A model of metabolic profile test applicable to this country where the average number of cows in a herd is small as to be fifteen is designed. Metabolic profiles as reflected in each parameter were discussed in relation to adequacy of dietary intake for production, milk production, reproductive performance, and diseases, and the possible measure to improve productivity of dairy cows were proposed. Much of the variation in parameters was due to differences between herds, and less to differences between seasons, differences between individual milk yield, and differences between lactational stages. As the average herd size in this country is small, it is believed that all the cows in a herd must be sampled, and the individual result of each parameter was compared with the standard limit for each lactational stage, and the percentage of cows which are outside the standard limits in a herd was calculated to use as a criteria for evaluation of the herd. Data outside the 99% confidential limits were to be deleted at first, but when the trends of the data outside the 99% confidential limits are same as the trends of the data within 99% confidential limits, the deleted data must be reviewed again, otherwise some important informations would be missed. The mean concentration of blood urea nitrogen in this study was much higher than that was reported in England, U.S.A. and Japan, and it was similar to the upper limits reported in England, U.S.A. and Japan. So it was thought that the concentration of blood urea nitrogen is improper as a criteria for protein intake. The increase of serum total protein cocentration beyond standard limits was due to increase of serum globulin concentration in most of the cows. The correlation coefficient between serum and protein and serum globulin concentration was 0.83. Serum globulin concentration was negatively related to adjusted corrected milk of herd. Serum albumin, calcium and magnessium concentrations were negatively related to adjusted corrected milk of herd, which indicate that high-producing individual or high-producing herd have not taken sufficient protein/amino acids, calcium and magnessium. Packed cell volume was negatively related to adjusted corrected milk of the herd, and the trend was same In each lactational stage. The correlation coefficient between serum and packed cell volume was 0.16 and the correlation was very weak. Blood glucose concentration was lowest in early lactational stage, which indicates negative energy balance in early lactational stage. Blood glucose concentration was negatively related to adjusted corrected milk of herd from peak to late lactational stage, which indicates negative energy balance during the period in high-producing individuals or high-producing herds. Correlation coefficient between serum aspartate aminotransferase activity and serum ${\gamma}$-glutamyltransferase activity was 0.41, and this indicates that serum ${\gamma}$-glutamyltransferase should be included as a parameter of metabolic profile test to evaluate liver function. Body condition score of dairy cows in this country was lower than that of Japan in every lactational stages, and the magnitude of increase in body condition score during middle and late lactational stages was small. Metabolic profile can not be evaluated with solely nutritional intake. When an individual or large percentage of cows in a herd have adnormal values In parameters of metabolic profile test, veterinary clinician and nutritionist should cooperate so as to diagnose diseases and to calculate the e of no운ents simultaneously.

• The Korean Journal of Nuclear Medicine
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• v.33 no.4
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• pp.413-421
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• 1999

Purpose: This study was performed to evaluate the usefulness of $^{99m}Tc$-HMPAO-labelled leucocyte scintigraphy for diagnosing prosthetic infection after total knee replacement arthroplasty without the aid of following bone marrow scintigraphy Materials and Methods: The study subjects were 25 prostheses of 17 patients (one man and 16 women, mean age. 65 years) who had total knee replacement arthroplasty. After injection of $^{99m}Tc$-HMPAO-labelled leucocyte, the whole body planar and knee SPECT images were obtained in all patients. The subjects were classified into three groups according to clinical suspicion of prosthetic infection. Group A (n=11) with high suspicion of infection; Group B (n=6) with equivocal suspicion of infection, and Group C (n=8) with asymptomatic contralateral prostheses. Final diagnosis of infection was based on surgical, histological and bacteriological data and clinical follow-up. Results: Infection was confirmed in 13 prostheses (11 in Group A and 2 in Group B). All prostheses in Group A were true positive. There were two true positives, one false positive and three true negatives in Group B, and six true negatives and two false positives in Group C. Overall sensitivity, specificity, and accuracy for diagnosis of the infected knee prosthesis were 100%, 75% and 88%, respectively Conclusion: $^{99m}Tc$-HMPAO-labelled leucocyte scintigraphy is a sensitive method for the diagnosis of infected knee prosthesis. However, false positive uptakes even in asymptomatic prosthesis suggest that bone marrow scintigraphy may be needed to achieve improved specificity.