• Proceedings of the Plant Resources Society of Korea Conference
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• 2003.04a
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• pp.61-62
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• 2003

Clonal propagation of high-value forest trees through somatic embryogenesis (SE) has the potential to rapidly capture the benefits of breeding or genetic engineering programs and to improve raw material uniformity and quality. A major barrier to the commercialization of this technology is the low quality of the resulting embryos. Several factors limit commercialization of SE for Corsican pine, including low initiation rates, low culture survival, culture decline causing low or no embryo production, and inability of somatic embryos to fully mature, resulting in low germination and reduced vigour of somatic seedlings. The objective was to develop a Corsican pine maturation medium that would produce cotyledonary embryos capable of germination. Treatments were arranged in a completely randomized design. Data were analyzed by analysis of variance, and significant differences between treatments determined by multiple range test at P=0.05. Corsican pine (Pinus nigra var. maritima) cultures were initiated on modified !P6 medium. Modifications of the same media were used for culture multiplication and maintenance. Embryogenic cultures were maintained on the same medium semi solidified with 2.5 g/l Gelrite. A maturation medium, capable of promoting the development of Corsican pine somatic embryos that can germinate, is a combination of iP6 modified salts, 2% maltose, 13% polyethylene glycol (PEG), 5 mg!l abscisic acid (ABA), and 2.5 g/l Gelrite. After initiation and once enough tissue developed they were grown in liquid medium. Embryogenic cell suspensions were established by adding 0.951.05 g of 10- to 14-day-old semisolid-grown embryogenic tissue to 9 ml of liquid maintenance media in a 250ml Erlenmeyer flask. Cultures were then incubated in the dark at 2022$^{\circ}$C and rotated at 120 rpm. After 2.53 months on maturation medium, somatic embryos were selected that exhibited normal embryo shape. Ten embryos were placed horizontally on 20 ml of either germination medium ($\frac{2}{1}$strength Murashige and Skoog (1962) salts with 2.5 g/l activated charcoal) or same medium with copper sulphate adjusted to 0.25 mg/1 to compensate for copper adsorption by activated carbon. 2% and 4% maltose was substituted by 7.5% and 13% PEG respectively to improve the yield of the embryos. Substitution of' maltose with PEG was clearly beneficial to embryo development. When 2% of the maltose was replaced with 7.5% PEG, many embryos developed to large bullet-shaped embryos. At latter stages of development most embryos callused and stopped development. A few short, barrel-shaped cotyledonary embryos formed that were covered by callus on the sides and base. When 4% of the maltose was removed and substituted with 13% PEG, the embryos developed further, emerging from the callus and increasing yield slightly. Microscopic examination of the cultures showed differing morphologies, varying from mostly single cells or clumps to well-formed somatic embryos that resembled early zygotic embryos only liquid cultures with organized early-stag. A procedure for converting and acclimating germinants to growth in soil and greenhouse conditions is also tested. Seedling conversion and growth were highly related to the quality of the germinant at the time of planting. Germinants with larger shoots, longer, straighter hypocotyls and longer roots performed best. When mature zygotic embryos germinate the root emerges, before or coincident with the shoot. In contrast, somatic embryos germinate in reverse sequence, with the cotyledons greening first, then shoot emergence and then, much later, if at all, the appearance of the root. Somatic seedlings, produced from the maturation medium, showed 100% survival when planted in a field setting. Somatic seedlings showed normal yearly growth relative to standard seedlings from natural seed.

• Education of Primary School Mathematics
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• v.16 no.3
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• pp.229-250
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• 2013

The purpose of this study is analyzing 'observation and recommendation letter by teacher', which is being submitted to screen and enhance the utilization of gifted students in accordance with recently introduced gifted students observation, recommendation and screening system. For the purpose, this study will provide with objective securing plan of 'observation and recommendation letter by teacher' by developing an optimum evaluation model. The research findings were as follows: First, the result of analysis on the mathematically gifted students behavior characteristic as appeared in 'observation and recommendation letter by teacher' suggested that the recommending teachers have the tendency of giving superficial statement instead of giving concrete case description. When it was analyzed for frequency by the 'observation and recommendation letter by teacher' analysis framework devised by the author, the teachers showed the tendency of concentrating on specific questions. Meanwhile, there was a tendency that teachers concentrate on specific gifted behavior characteristic or area for which concrete case had been suggested. The reason is believed that such part is easy to observe and state while others are not, or, teachers did not judge the other part as the characteristic of gifted students. Second, the gifted students behavior characteristics as appeared in 'observation and recommendation letter by teacher' were made into scores by Rubric model. When the interrater reliability was analyzed based on these scores, the correlation coefficient of 1st scoring was .641. After a discussion session was taken and 2nd scoring was done 3 weeks later, the correlation coefficient of 2nd scoring increased to .732. The reason is believed that; i) the severity among scorers was adjusted by the discussion session after the 1st scoring, ii) the scorers established detail judgment standard on various situations which can appear because of the descriptive nature, and, (iii) they found a consensus on scoring for a new situation appeared. It implies that thorough understanding and application of scorers on evaluation model is as important as the development of optimum model for the differentiation of mathematically gifted elementary students.

• Journal of Biomedical Engineering Research
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• v.21 no.3 s.61
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• pp.321-331
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• 2000

Multiple 15-hue tests were designed and implemented on a PC in the study so as to quickly and quantitatively evaluate color vision acuity. Difficulty of the test was control)ed by the value of CDBACC (color difference between adjacent color chips) calculated using a CIELAB formula. The multiple 15-hue tests consist of eight of the hue tests (test 3-10) and three of the basic color (red, green, blue) tests (test 11-13). The 15 colors used for the hue tests were specified by the 15 color coordinates that were located at a constant distance (d = 2. 3. 5. 7, 10, 20, 30. 40) from white reference in the CIE chromaticity coordinate system and were separated by a constant color difference (CDBACC = 0.75, 1.1, 1.8. 2.5. 3.5. 7.5. 11, 14) from the adjacent chips. The color coordinates for the 15 chips for the basic color tests were the same as those of the 15 points spaced equally by a constant color difference (6.87 for the green color test. 7.27 for the red color test, 7.86 for the blue color test) from the white reference along the axis of red, green and blue. Thirty normal subjects who were not color blind were taken to undergo the multiple 15-hue tests. It was observed that most of the subjects correctly arranged color chips for the tests with CDBACC greater than 5, whereas no one correctly answered for those with CDBACC less than 2. Rapid changes in the number of the subjects correctly arranged took place when CDBACC of the tests was between 2 and 4.5. In the basic color tests, unlike the hue tests having similar values of CDBACC, it was seen that the subjects arranged color chips even less correctly. It was found that JNCD (just noticeable color difference) - a measure of color vision acuity was about 3 in average for the subjects. The JNCD was chosen as the value of the CDBACC of the test for which about $50\%$ of the subjects failed to successfully arrange color chips. ERCCA (error rate of color chips arrangement) for the test with CDBACC the same as the JNCD was shown to be about $20\%$. It is expected that the multi 15-hue tests implemented on a PC in the study will be an economical tool to quickly and quantitatively evaluate color vision acuity and, accordingly, the tests can be used for early diagnosis to massive potential patients suffering from diseases (ex. diabetes, glaucoma) which may induce changes in color vision acuity.

• Journal of Life Science
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• v.16 no.1
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• pp.131-135
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• 2006

Oligopeptide is known to be an essential nitrogen nutrient for bacterial growth. Oligopeptide can be transported into cytoplasm by a specific transport system, Opp system. Opp system is composed of five proteins, which are transcribed by an operon. These are responsible for oligopeptide binding protein (OppA), permease (OppB and OppC) and energy generation system (OppD and OppF), respectively. Previously, we isolated the opp operon from Vibrio fluvialis and constructed the oppA mutant by allelic exchange method. In this study, we investigated the growth pattern and biofilm production under the different growth condition. When the cells were cultivated using brain heart infusion(BHI) medium, the wild type was faster than the mutant in growth during the exponential phase. However, it showed that the growth pattern of two strains in M9 medium is very similar. The growth of wild type showed better than that of the mutant grown at pH 8. At pH 7, there was no an obvious difference in growth. After 5 mM $H_2O_2$ was treated to the cells $(OD_{600}=1.2)$, the cell survival was examined. The oppA mutation did not affect in survivability. In the presence of $10{\mu}g/ml$ polymyxin B, the biofilm production of the oppA mutant was higher than that of the wild type.

• Journal of Elementary Mathematics Education in Korea
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• v.13 no.2
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• pp.163-192
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• 2009

Currently, our country operates gifted education only as a special curriculum, which results in many problems, e.g., there are few beneficiaries of gifted education, considerable time and effort are required to gifted students, and gifted students' educational needs are ignored during the operation of regular curriculum. In order to solve these problems, the present study formulates the following research questions, finding it advisable to conduct gifted education in elementary regular classrooms within the scope of the regular curriculum. A. To devise a teaching plan for the gifted students on mathematics in the elementary school regular classroom. B. To develop a learning program for the gifted students in the elementary school regular classroom. C. To apply an in-depth learning program to gifted students in mathematics and analyze the effectiveness of the program. In order to answer these questions, a teaching plan was provided for the gifted students in mathematics using a differentiating instruction type. This type was developed by researching literature reviews. Primarily, those on characteristics of gifted students in mathematics and teaching-learning models for gifted education. In order to instruct the gifted students on mathematics in the regular classrooms, an in-depth learning program was developed. The gifted students were selected through teachers' recommendation and an advanced placement test. Furthermore, the effectiveness of the gifted education in mathematics and the possibility of the differentiating teaching type in the regular classrooms were determined. The analysis was applied through an in-depth learning program of selected gifted students in mathematics. To this end, an in-depth learning program developed in the present study was applied to 6 gifted students in mathematics in one first grade class of D Elementary School located in Nowon-gu, Seoul through a 10-period instruction. Thereafter, learning outputs, math diaries, teacher's checklist, interviews, video tape recordings the instruction were collected and analyzed. Based on instruction research and data analysis stated above, the following results were obtained. First, it was possible to implement the gifted education in mathematics using a differentiating instruction type in the regular classrooms, without incurring any significant difficulty to the teachers, the gifted students, and the non-gifted students. Specifically, this instruction was effective for the gifted students in mathematics. Since the gifted students have self-directed learning capability, the teacher can teach lessons to the gifted students individually or in a group, while teaching lessons to the non-gifted students. The teacher can take time to check the learning state of the gifted students and advise them, while the non-gifted students are solving their problems. Second, an in-depth learning program connected with the regular curriculum, was developed for the gifted students, and greatly effective to their development of mathematical thinking skills and creativity. The in-depth learning program held the interest of the gifted students and stimulated their mathematical thinking. It led to the creative learning results, and positively changed their attitude toward mathematics. Third, the gifted students with the most favorable results who took both teacher's recommendation and advanced placement test were more self-directed capable and task committed. They also showed favorable results of the in-depth learning program. Based on the foregoing study results, the conclusions are as follows: First, gifted education using a differentiating instruction type can be conducted for gifted students on mathematics in the elementary regular classrooms. This type of instruction conforms to the characteristics of the gifted students in mathematics and is greatly effective. Since the gifted students in mathematics have self-directed learning capabilities and task-commitment, their mathematical thinking skills and creativity were enhanced during individual exploration and learning through an in-depth learning program in a differentiating instruction. Second, when a differentiating instruction type is implemented, beneficiaries of gifted education will be enhanced. Gifted students and their parents' satisfaction with what their children are learning at school will increase. Teachers will have a better understanding of gifted education. Third, an in-depth learning program for gifted students on mathematics in the regular classrooms, should conform with an instructing and learning model for gifted education. This program should include various and creative contents by deepening the regular curriculum. Fourth, if an in-depth learning program is applied to the gifted students on mathematics in the regular classrooms, it can enhance their gifted abilities, change their attitude toward mathematics positively, and increase their creativity.

• Journal of Embryo Transfer
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• v.18 no.1
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• pp.69-73
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• 2003

This study was undertaken to investigate the effect of three different porcine IVM media, TCM-199, mSOF and NCSU-23 on early development of porcine spontaneous parthenogenotes. Spontaneous parthenogenotes were induced by a prolonged culture of porcine oocytes in each medium. In Experiment 1, oocytes derived from gilts were matured in three IVM media and maturation of oocytes was evaluated by the status of chromatin configuration. Oocytes matured in mSOF, NCSU-23 and TCM-199 showed no significant difference (P>0.05) in maturation. Maturation rates at 48h after IVM were 83.1$\pm$2% (mSOF), 78.0$\pm$3% (NCSU-23) and 83.5$\pm$2% (mSOF), 78.0$\pm$3% (NCSU-23) and 83.5$\pm$2% (TCM-199). In Experiment 2, pronucleus formation and development to 6~8 cell stage of pig oocytes activated spontaneously. Pronucleus formation, cleavage rate and development to 6~8 cell embryos of porcine spontaneous parthenogenotes were assessed at 55~58 h, 96 h and 168h after IVM, respectively. Pronucleus formation (5.4$\pm$2% and 3.7 $\pm$ 1% vs 1.7 $\pm$ 3%) and development to the 6$\pm$8 cell (3.2$\pm$3% and 4.0$\pm$1% vs 1.4$\pm$3%) was significantly (P<0.05) higher in mSOF or NCSU-23 than TCM-199. In conclusion, the present study showed that oocytes matured in mSOF and NCSU-23 were spontaneously activated with higher frequency.

• Journal of Embryo Transfer
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• v.29 no.3
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• pp.265-271
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• 2014

Implementation of smart embryo technologies in cattle e.g. ovum pick-up followed by in vitro embryo production (OPU-IVP). Seasonal variation is important factor for follicular growth, oocytes quality, quantity and developmental competence. Therefore the aim of present study was carried out to investigated whether the seasons (hot and cool) effect on follicular development, oocyte recovery and subsequent embryo development. Follicular oocytes were aspirated from Korean native cows (Hanwoo) by the ovum pick-up (OPU) method, which was performed 24 times during two different seasons, the hot (July to September) and cool (October to December), from OPU donors. The recovered oocytes were classified according to morphological categories and used for in vitro embryo production (IVEP). The mean number of total follicles was significantly higher (p<0.05) during the hot season ($18.32{\pm}2.26$) compared to cool season ($15.41{\pm}3.34$). Furthermore, seasons did not significantly effect on the number of oocytes recovered (hot season: 41.16% vs. cool season: 46.14%). However, the average number of Grade A oocytes was significantly greater during hot ($1.75{\pm}1.86$) season compared to the cool season ($1.00{\pm}1.46$), but there was no significant difference of other grades oocytes. The cleavage rate (hot: 66.67% vs. cool: 63.3%) and embryo development (hot: 58.95% vs. cool: 56.97%) did not differ significantly between the seasons. In conclusion, the results of present study suggest that the season (hot and cool) does not have effects on the oocyte recovery and embryo developmental competence of in vitro cultured embryos.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.6 s.165
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• pp.837-847
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• 2007

1,098 pieces of photographs($1995{\sim}2002$) of men's suit style have been classified according to fashion images in order to examine features and change aspects with statistical analysis. The findings of examining features of the trend by year with test of homogeneity, correspondence analysis, biplots, correlation analysis and regression analysis are as follows: (a) there are significant differences on fashion images as the trend by yew with test of homogeneity, (b) there are remarkable differences on the fashion trend by year with correspondence analysis and biplots. (c) There are significant correlations for appearance among fashion images by its frequency through correlation analysis, and (d) it is assumed that fashion images are going to be gradually outstanding according to regression analysis.

• Korean Journal of Animal Reproduction
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• v.26 no.2
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• pp.125-132
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• 2002

This study was conducted to examine the effects of electric stimulation conditions on in vitro developmental ability of procine embryos after somatic cell nuclear transfer, The porcine ear cell was cultured in vifro for confluency in serum-starvation condition (TCM-199＋0.5% FBS) for cell confluency. The zona pellucida of IVM oocytes were partially drilled using laser system. Single somatic cell was individually transferred into the enucleated oocyte. The reconstructed embryos were electrically fused with 0.3M mannitol. After electric fusion, the embryos were activated and cultured in NCSU-23 medium containing 10% FBS at 39$^{\circ}C$, 5% $CO_2$ in air for 6 to 8 days. Nuclear transferred(NT) oocytes which fused at a field strength of 1.90kv/cm showed a higher (P<0.05) fusion rate(49.5%, 50/101) compared to 2.10 kv/cm(25.8%, 24/93) or 2.50kv/cm(30.3%, 27/89). After electric activation, the cleavage rate of NT embryos was 48.0(24/50), 66.6(16/24) and 70.3% (19/27), respectively and these were not different. There was no significant difference in fusion rate by duration and pulse of electric stimulation. In cleavage rate, however, more NT embryos(76.3%, 45/59) cleaved at 60 $\mu$sec twice than other embryos(49.1 to 56.5%) with different conditions of electric stimulation(P<0.05). NT embryos activated at a field strength of 1.50kv/cm showed a higher developmental rate(9.8%, 5/51) than those embryos activated at 1.25kv/cm(0%) or parthenotes(6.4%, 7/109). These results suggest that some factors such as field strength, duration and pulse of electric stimulation could be affected to in vitro developmental ability of nuclear transplanted porcine embryos.

• Journal of Animal Science and Technology
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• v.46 no.2
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• pp.227-234
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• 2004

This experiment was conducted at Cheonan Yonam Experimental Livestock Farm in 2001-2002 to detennine the effect of harvest date(20 April, 26 April and 4 May) on forage yield and quality of rye varieties of three different maturing groups(early maturing variety = ‘Koolgrazer’ midseason maturing variety = ‘Horni122’ and late maturing variety = ‘Danko’). The heading date of Kooigrazer, Hornil22 and Danko were 17, 22 and 29 April, respectively. Dry matter percentage increased from 15.6 to 21.6% as the harvest date was delayed from April 20 to May 4. Among the rye varieties tested, dry matter percentage of Koolgrazer, Hornil22 and Danko were 20.9, 18.8 and 16.3%, respectively. Dry matter yield increased from 1l.2 to 13.9 ton/ha as the harvest date was delayed, but no significant difference among rye varieties. As the harvest date was delayed, total digestible nutrients(TDN) yield also increased significantly from 7.4 to 8.4 ton/ha However no significant difference was found among rye varieties. Crude protein(CP) percentage decreased from 20.3 to 17.1% as the harvest date was delayed, and CP percentage of late maturing variety, Danko, was significantly higher than that of the other varieties. In content of fiber component(NDF, ADF, ADL, hemicellulose and cellulose) of rye, the late harvest date(4 May) showed the highest among harvest dates. From comparisoo within rye varieties tested, Kooigrazer, a early maturing variety had higher than a rnidseason and late maturing varieties, Hornill22 and Danko. The cellulase digestible of organic matter of dry matter(CDOMD) decreased as the harvest date was delayed. Among the rye varieties tested, the CDOMD of a early maturing variety, Koolgrazer was the lowest. Our study differences of winter rye in forage yield and quality resulting from variety maturity and harvest stage. A early maturing variety, Kooigrazer should be harvested between 24 and 28 April, Hamill 22(midseason maturing variety) harvested between 29 April and 3 May, Danko(late maturing variety) harvested between 4 and 8 May for maximum forage yield and optimum quality.