• Journal of Life Science
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• v.26 no.10
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• pp.1121-1129
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• 2016

High-molecular-weight glutenin subunits (HMW-GSs) are extremely important determinants of the functional properties of wheat dough. Transgenic rice plants containing a wheat TaGlu-Ax1 gene encoding a HMG-GS were produced from the Korean wheat cultivar ‘Jokyeong’ and used to enhance the bread-making quality of rice dough using the Agrobacterium-mediated co-transformation method. Two expression cassettes with separate DNA fragments containing only TaGlu-Ax1 and hygromycin phosphotransferase II (HPTII) resistance genes were introduced separately into the Agrobacterium tumefaciens EHA105 strain for co-infection. Rice calli were infected with each EHA105 strain harboring TaGlu-Ax1 or HPTII at a 3:1 ratio of TaGlu-Ax1 and HPTII. Among 210 hygromycin-resistant T₀ plants, 20 transgenic lines harboring both the TaGlu-Ax1 and HPTII genes in the rice genome were obtained. The integration of the TaGlu-Ax1 gene into the rice genome was reconfirmed by Southern blot analysis. The transcripts and proteins of the wheat TaGlu-Ax1 were stably expressed in rice T₁ seeds. Finally, the marker-free plants harboring only the TaGlu-Ax1 gene were successfully screened in the T₁ generation. There were no morphological differences between the wild-type and marker-free transgenic plants. The quality of only one HMW-GS (TaGlu-Ax1) was unsuitable for bread making using transgenic rice dough. Greater numbers and combinations of HMW and LMW-GSs and gliadins of wheat are required to further improve the processing qualities of rice dough. TaGlu-Ax1 marker-free transgenic plants could provide good materials to make transgenic rice with improved bread-making qualities.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.27 no.3
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• pp.45-53
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• 2019

The purpose of this study is to provide a brief overview of the helicopter pilot training system applied to the Army, and to examine what factors positively affect the successful flight training of helicopter pilots. For this purpose, we analyzed the correlations between various factors such as individual characteristics, selection factors, flight aptitude evaluation, theoretical subjects test, and self-life evaluation. As a result, it was found that only the flight experience was influential on the individual characteristics at the beginning of the training course, and the learning achievement represented by the test of theoretical subjects was positively influenced throughout the flight training course. This reaffirms the fact that an individual's high level of motivation or effort influences his flight training performance. These results are expected to be useful indicators for future development of pilot selection system and pilot training system.

• Journal of Korean Elementary Science Education
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• v.38 no.2
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• pp.216-233
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• 2019

The purpose of this study was to identify the aspects of elementary school students' interactions shown conceptual changes in collaborative scientific argumentation. Fifty sixth graders of an elementary school in Jeonju were selected for this study. Ten small groups consisting of five students each were organized evenly with considerations of their gender, science achievement, scientific discussion experience and degree of communication apprehension. 'Food web and Ecosystem' and 'Change of Moon shape' were selected as the proper topics of collaborative scientific argumentation in terms of difficulty to be understanded by the $6^{th}$ graders. The small group's dialogue was recorded. The students' activity sheets, field note and interviews of the participants were collected. Based on the collected data, we analyzed the aspect of small groups' interaction shown conceptual change of each student. The result of this study was as follows: The interaction aspects of the small group of students who showed conceptual changes in the collaborative scientific discussion have a tendency of showing their discussion responses, explanation-opposition discourse, the use of rigorous criteria, their collaborative attitude and participation.

• Journal of The Korean Association For Science Education
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• v.29 no.5
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• pp.541-551
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• 2009

This study aimed to investigate the effect of pre-service science teachers' experiences in nuclear physics research on their understanding of scientific inquiry process and career planning. The thirty-week URP (Undergraduate Research Participation) program was designed with the participation of six pre-service science teachers. Data sources included in-depth interviews with the individual teachers, group discussions, participant observations with field notes over the weeks, journals and lab logs, etc. Results indicated that the teachers perceived the complex and repetitive nature of the science research process, the importance of scientists' creativity and collaboration, etc. Their typical impressions of scientists has also more or less changed. In addition, the teachers had opportunities to confirm their aptitude in physics and to explore their career options in physics-related fields.

• Journal of The Korean Association For Science Education
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• v.41 no.2
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• pp.145-154
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• 2021

This study aims to investigate teachers' perceptions of the composition of high school science elective courses ahead of the 2022 curriculum revision, and to derive implications for the organization of the 2022 revised science curriculum in preparation for the full implementation of the high school credit system. To this end, a survey was conducted by randomly sampling high schools across the country. A total of 192 science teachers responded to the questionnaire. In addition, 12 high school science teachers were selected as a focus group, and in-depth interviews were conducted to investigate opinions on the restructuring of elective courses in science. Main research results include 129 (67.2%) science teachers in the survey answered that the current 2015 curriculum's science and elective courses system should be maintained. In the next curriculum, when reconstructing science elective subjects, it is necessary to provide an opportunity to experience the entire contents of each science field through Science I·II system as before, and to ensure student choice in preparation for the credit system. In addition, the opinion that general elective subjects should be organized to include all the contents of science I and II subjects was the highest. Through in-depth interviews, science teachers emphasized that the current science I subject system allows access to the content areas of science as much as possible as the number of subjects is small, and that subjects, such as physics, where the hierarchy of concepts is important, should deal with important content within one subject rather than divided by area. On the other hand, in the current I subject system, there is no subject for liberal arts students to choose from, so teachers suggested that science electives should be organized by subdividing each content area. Based on the research results, the necessity of organizing high school science elective courses in consideration of the purpose of the high school credit system, ways to organize science-convergence elective courses as subjects for all students regardless of career aptitude, ways to organize science-career elective courses, and ways to organize science elective courses in connection with the college admission system were proposed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.7
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• pp.908-913
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• 2008

This study was carried out to investigate the effects of Salicornia herbacea L. on baking properties of white breads. Crude fiber and crude ash contents of Salicornia herbacea L. powder were 70.02% and 25.6%, respectively. Fe and Ca contents of Salicornia herbacea L. were 176 ppm and 1,175 ppm, respectively. The pH of dough with Salicornia herbacea L. powder was similar to that of control. Salinity contents did not show any significantly differences between bread added Salicornia herbacea L. powder and control. L (lightness) and b (yellowness) value of the dough were decreased by the addition of Salicornia herbacea L., but a (redness) value was increased. The volume of dough during fermentation and the baking loss did not show significant difference between treatments and control. The weight of bread was increased by the addition of Salicornia herbacea L. but the volume was not.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.8 no.2
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• pp.85-89
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• 1975

Heavy metal content have been determined in baby clams from March 1973 to April 1974 in Depori, Samchunpo, Korea. Monthly changes of mercury, lead, copper ana cadmium in the samples were irregular but as a whole, the content of mercury, lead, copper and cadmium were relatively high in summer season. The content of total mercury, lead, copper and cadmium in the samples ranged from 0.003 to 0.038 ppm, 0.096 to 0.931 ppm, 0.023 to 0.139 ppm and 0.009 to 0.038 ppm respectively. In the consideration of heavy metal content, it was concluded that baby clams in Depori, Samc hunpo, Korea is suitable for processing materials.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1301-1306
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• 1998

This study was conducted to investigate the effect of soybean protein isolate (SPI) on the properties of noodle which was made of composite flour blended with SPI extracted at acidic (pH 2.0, 3.0), neutral (pH 7.0) and alkaline (pH 10.0, 12.0) conditions. L-value of dry and cooked-moodle which were made of composite flour was lower than that of 100% wheat flour, but a and b-value wete higher than those of 100% wheat flour, Optimal cooking time of dry-noodle which was made of composite flour was longer than that of 100% wheat flour, but the weight, volume and water absorption of the cooked-noodle were lower than those of cooked-noodle of 100% wheat flour. Breaking force of dry-noodle which was made of composite flour blended with $SPI-2,\;SPI_3,\;SPI_{7}$, and $SPI-{10}$ was lower than that of 100% wheat flour, but the breaking force of dry-noodle which was made of composite flour blended with $SPI-{12}$ at level of 5% and 10% was same as that of 100% wheat flour. Springiness and cohesiveness of the cooked-noodle which was made of composite flour were same as those of 100% wheat flour, but chewiness and hardness were higher than those of 100% wheat flour.

• Korean Journal of Food Science and Technology
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• v.12 no.3
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• pp.205-208
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• 1980

Protein content and amino acid composition of three prospective Korean wheat varieties (Youngkwang, Wonkwang and Chokwang) were studied from the viewpoint of baking performance. 1. Protein contents of Korean varieties were Less than 10% which were relatively lower than the U. S. baking standard. These levels were considered insuffcient for best baking performance. 2. Compared to U. S. baking standard, Korean wheat varieties showed slightly lower level of glutamic acid, which is considered to play an important role in baking performance of flour. Approximately 25% decrease in glutamic acid content was observed in Korean varieties when the absolute amount of glutamic acid per unit sample size was compared. 3. Korean wheat varieties showed similar levels of proline and cystine, slightly higher levels of lysine, ammonia and aspartic acid; and slightly lower level of essential amino acids compared to the U. S. baking standard. 4. Protein content and amino acid composition of Korean wheat varieties were considered to be intermediate of U. S. baking and cookie standards. From this viewpoint, Youngkwang showed the greatest potential for best baking performance among Korean varieties.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.1
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• pp.44-51
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• 1985

The changes of the get forming ability of common carp (Cyprinus carpio) and conger eel (Astroconger myriaster) meat during ice and frozen storage were investigated in connection with the other quality indices, such as pH, K-value, VBN, viable cell count and sensory evaluation. The shelf-life of iced common carp and conger eel as the raw materials for fish jelly product was considered to be about 16 and 13 days, respectively. Little change in gel forming ability of two species was found during frozen storage at $-30^{\circ}C$ for 3 months. From the results obtained in the examination on the gel forming abilities of the two species stored at $-30^{\circ}C$ for 3 months were superior to those stored in ice for 3 to 4 and 4 to 6 days individually. Fish jelly from the common carp was much more elastic than that of conger eel meat. The overall qualities of two species held in frozen storage as the raw material for fish jelly product were excellent.