• Journal of Radiation Protection and Research
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• v.23 no.2
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• pp.83-88
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• 1998

Chitosan is a nontoxic natural chealtor which was made by chitin, and reduced a contamination of radiostrontium in animals. In this experiment, A different molecular weight of C-14 chitosan was intravenously administered to mice, and then the distribution of C-14 chitosan in the body was observed. Male mice (8 to 10 weeks, body weight of 30 to 35g) of ICR strain were used. C-14 chitosan was diluted with saline and then given intravenously in mice. After the administration of C-14 chitosan, mice was sacrificed at the 6th hour, 1st, 3rd, 5th, and 7th day. Beta radioactivities in the blood, liver, kidney, liver, muscle, testis, and urine was measured using a liquid scintillation analyzer. Most of the C-14 chitosan was excreted through urine within 6 hours. Biodistribution of C-14 chitosan was similar despite the difference of moleclar weight. Higher distributions of radioactivities were found in the liver, kidney, spleen. The relative concentration in tissue increased for the 6 hours and then decreased. In conclusion, most of C-14 chitosan was excreted through urine despite the difference of molecular weight. and, low molecular weight of C-14 chitosan showed higher distribution than high molecular weight of C-14 chitosan in tissues.

• Journal of The Korean Association For Science Education
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• v.38 no.6
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• pp.901-917
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• 2018

The purpose of this study is to develop the questionnaire on pre-service elementary teachers' recognition of self-understanding and change capacity for science education and to investigate their recognitions with it. At the beginning of the study, we made a tool to investigate the self-understanding and change capacity of pre-service elementary teachers through literature review and discussions. The former half of the questionnaire was related to self-understanding with factors such as 'self-concept clarity,' 'career identity' and 'self-efficacy:' 'self-understanding as a pre-service elementary teacher' (12 items) and 'self-understanding as a pre-service elementary science teacher' (12 items). Its latter half was about the change capacity with factors such as 'change sensitivity,' 'goal consciousness,' 'collaboration,' 'reflection,' and 'mastery.' It consisted of three parts: 'general change capacity,' 'change capacity as a pre-service elementary teacher' and 'change capacity as a pre-service elementary science teacher' with 17 items, respectively. With this tool, we surveyed 153 pre-service elementary teachers. The results are as follows: First, pre-service elementary teachers have a positive recognition about self-understanding and change capacity, but the recognition of self-understanding and change capacity as pre-service elementary science teachers were relatively less positive. Second, factors of self-understanding and change capacity as pre-service elementary science teachers have a significant correlation with each other. Especially, there was a high correlation between 'self-efficacy' of self-understanding and 'goal consciousness' and 'mastery' of change capacity. Based on these results, some implications for self-understanding and change capacity related to science education were discussed.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.16 no.4
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• pp.397-410
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• 2018

When considering the long-term safety assessment of spent-nuclear fuel management, americium is one of the most radio-toxic actinides. Although spectroscopic methods are widely used for the study of actinide chemistry, application of those methods to americium chemistry has been limited. Herein, we purified $^{241}Am$ to obtain a highly pure stock solution required for spectroscopic studies. Quantitative and qualitative analyses of purified $^{241}Am$ were carried out using liquid scintillation counting, and gamma and alpha radiation spectrometry. Highly sensitive absorption spectrometry coupled with a liquid waveguide capillary cell and time-resolved laser fluorescence spectroscopy were employed for the study of Am(III) hydrolysis and oxalate (Ox) complexation. $Am^{3+}$ ions under acidic conditions exhibit maximum absorbance at 503 nm, with a molar absorption coefficient of $424{\pm}8cm^{-1}{\cdot}M^{-1}$. $Am(OH)_3(s)$ colloidal particles formed under near neutral pH conditions were identified by monitoring the absorbance at around 506-507 nm. The formation of ${Am(Ox)_3}^{3-}$ was detected by red-shifts of the absorption and luminescence spectra of 4 and 5 nm, respectively. In addition, considerable enhancements of the luminescence intensities were observed. The luminescence lifetime of ${Am(Ox)_3}^{3-}$ increased from 23 to 56 ns, which indicates that approximately six water molecules are replaced by carboxylate ligands in the inner-sphere of the Am(III). These results suggest that ${Am(Ox)_3}^{3-}$ is formed through the bidentate coordination of the oxalate ligands.

• The Journal of Korean Academy of Prosthodontics
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• v.57 no.3
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• pp.263-270
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• 2019

Current trends in restorative dentistry focus on improving the esthetics and keeping the sound dental tissues as long as possible. The aims of this case report were to describe the successful outcome of cubic-phase zirconia laminate veneers for a patient with isolated microdontia by using a digital workflow, and to describe their clinical implications. A 15-year-old female who had isolated microdontia in combination with spacing visited Ajou University Dental Hospital for esthetic treatment. In this case, 6 maxillary anterior teeth were restored with cubic-phase zirconia laminate veneers without tooth structure removal by using a digital impression, computer-aided design (CAD) software, and computer-aided manufacturing (CAM) procedures. At 6-month follow-up, no distinct mechanical and biological complications were detected and the prostheses exhibited satisfactory esthetics and functions. Due to its favorable tissue responses and enhanced translucency, cubic-phase zirconia can be a suitable strategy for a noninvasive esthetic approach.

• Journal of The Korean Association For Science Education
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• v.39 no.2
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• pp.279-293
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• 2019

This study investigated the effects of national science leading school programs on students' positive experiences about science (PES) and teachers' perceptions of curriculum implementation factors affecting students' PES. For this study, Test for Indicators of Positive Experiences about Science (TIPES) was administered to a total of 11,488 students from 117 national science leading schools and 1,315 students from 50 normal counterpart schools. In addition, a total of 105 teachers were given a survey asking their curriculum implementation levels and perceptions on importance and performance levels of each identified factor that was known to influence students' PES. Students' total PES scores and scores in five sub-components of PES were widely varied across science leading school program types. In general, participating teachers reported common curriculum implementation factors that most positively affected students' PES including 'science-related activities out of school,' 'student-centered research projects,' 'ICT-related materials' and 'performance assessment.' Based on these results, implications for science education were discussed.

• 한국노년학
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• v.32 no.3
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• pp.819-834
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• 2012

The purpose of this study was to examine the degree of successful aging and to investigate influencing factors of it in elderly to types of gender. Subjects were 73 male elderly and 77 female elderly, total 150 elderly living at K city in C province, from May to June, 2012. The data were analyzed using the SPSS Win 18.0 program for $X^2$ test, t-test, Pearson's correlation coefficients and multiple regression analysis. The correlated factors of successful aging among male elders included life satisfaction(r=.525, p<.001), family support(r=.355, p=.004), depression(r=-.555, p<.001) and loneliness(r=-.437, p<.001). Those of successful aging among female elders included life satisfaction(r=.607, p<.001), leisure satisfaction(r=.679, p<.001), family support(r=.784, p<.001), depression(r=-.516, p<.001), loneliness(r=-.644, p<.001) and self-transcendence(r=.576, p<.001). Life satisfaction and depression were statistically significant influencing factors of successful aging in male elders. Especially in the cases of female elders, life satisfaction, depression, family support and self-transcendence affected to successful aging. Life satisfaction, depression, family support, and self-transcendence were explained 52.9% in perception of successful aging among elders. This study suggests that life satisfaction, depression, family support, and self-transcendence will be considered in enhancing the successful aging promoting care and welfare designed for types of gender.

• The Journal of the Korea Contents Association
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• v.22 no.1
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• pp.620-628
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• 2022

The purpose of this study is to confirm the degree of improvement in performance confidence and executive ability after conducting field adaptation education to dental hygiene students who start their first field practice. Thirty dental hygiene students were evaluated with performance confidence, indirect and direct evaluation of practical skill before and after the field adaptation education was conducted for 15 hours. Also field practice satisfaction was investigated after field practice. A paired t-test was conducted to compare performance confidence, indirect executive ability, and direct practical ability before and after education. Pearson's correlation was performed on the correlation between field adaptation education and field practice satisfaction. Linear regression analysis was performed to identify the influencing factors of field practice satisfaction. As a results, performance confidence, indirect and direct practical skills of after field adaptation program were increased than before that(p<0.05). The correlation between field adaptation education and field practice satisfaction showed that "education satisfaction" among the field adaptation education sub-regions correlated with "education content" and "support of field practice" among the field practice satisfaction sub-regions(p<0.05). Therefore, it is necessary to develop and management various adaptation education in the future as it increases the adaptability of the first field practice and increases the satisfaction of field practice.

• Journal of Industrial Convergence
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• v.20 no.5
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• pp.125-134
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• 2022

This study was conducted to improve the direction of extracurriculular education for health students and to establish and systematic extracurricular education and operation system. The needs and priorities of extracurricular education programs were investigated through a survey of health students. The data were analyzed by Borich's needs and The Locus for Focus Model. As a result of priorities of extracurriculular programs according to Borich's needs, the top 10 programs included 'certification', 'career exploration', 'overseas service', 'second language', 'employment education', 'talent donation', 'English', 'computer utilization', and 'major convergence learning'. As a result of priorities by applying The Locus for Focus Model, 'certification', 'career exploration', 'employment education', 'foreign service', 'English', 'domestic service', 'second foreign language', 'talent donation', and 'computer utilization' was included. A total of nine programs were derived by combining Borich and The Locus for Focus Model, and priorities were 'certification', 'career exploration', 'overseas service', 'second foreign language', 'employment education', 'talent donation', 'English', 'computer utilization', and 'domestic service'. As a result of this study, health students had a high needs for comparison programs for employment and volunteer programs, so universities should reflect this and establish a comparison program operation system for health students.

• Journal of Industrial Convergence
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• v.20 no.8
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• pp.137-144
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• 2022

This study was conducted to provide the basis for psychological management direction of students ahead of their first field practice by grasping the degree of anxiety and confirming the relationship between departments satisfaction and practice expectations. A survey was conducted on dental hygiene students ahead of their first field practice and 135 people were selected as final analysis subjects. Data analysis investigated general characteristics, department satisfaction, field practice expectation and pre-education satisfaction and statistical analysis was conducted through mean(±SD), one-way ANOVA, and multiple linear regression analysis method. As a result, the anxiety level was high in the lower group of performance in the previous semester, and the department satisfaction and pre-education satisfaction were high in the group with low anxiety level. As a result of the correlation analysis, it was found that department satisfaction, field practice expectation, pre-education satisfaction, and anxiety were negatively correlated, and the higher the practice expectation, the lower the anxiety. Therefore, in order to lower the level of anxiety before field practice, it is necessary to come up with measures to increase interventional pre-education, department satisfaction and field practice expectation.

• Journal of The Korean Association For Science Education
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• v.43 no.4
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• pp.403-414
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• 2023

In this study, we examined the adaptive practices of science teachers in their classrooms and their perspectives on the distinguishing features of these practices within science subjects. Our analysis comprised 339 cases from 128 middle and high school science teachers nationwide, and 199 cases on the characteristics of adaptive practices in science disciplines. The primary findings were as follows: First, the most significant characteristic of adaptive practice in science disciplines pertained to experimental procedures. Within the 'suggestion of additional materials/activities' category, the most frequently cited adaptive practice, teachers incorporated demonstrations to either facilitate student comprehension or enhance motivation. Additionally, 'experimental equipment manipulation or presentation of inquiry skills' emerged as the second most common adaptive practice related to experiments. Notably, over 50% of teacher responses regarding the characteristics of adaptive practices in science pertained to experiment guidance. Second, many adaptive practices involving difficulties experienced by students in learning situations were presented, particularly in areas such as numeracy and literacy. Many cases were related to the basic ability of mathematics used as a tool in science learning and understanding scientific terms in Chinese characters. Third, beyond 'experiment guidance', the characteristic adaptive practices of science subjects were related to 'connections between scientific theory and the real world', 'misconception guidance in science', 'cultivation of scientific thinking', and 'convergence approaches'. Fourth, the cases of adaptive practice presented by the science teachers differed by school level and major; therefore, it is necessary to consider school level or major in future research related to adaptive practice. Fifth, most of the adaptive action items with a small number of cases were adaptive actions executed from a macroscopic perspective, so it is necessary to pay attention to related professionalism. Finally, based on the results of this study, the implications for science education were discussed.