• Journal of Plant Biotechnology
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• v.40 no.3
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• pp.147-155
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• 2013

In this experiment, we report for the first time mass propagation by in vitro mircrotuberization of Codonopsis lanceolata. We first examined the effect of cytokinins on multiple shoot induction. 2.0 $mg{\cdot}L^{-1}$ of kinetin not only gave the highest rate of shoot induction (19.1%) but also the elongation of shoot (17.1 mm). Secondly, we investigated the effect of sugars on in vitro microtuberization from nodal segments. The diameter of tuberous roots was enlarged in the half-strength MS medium supplemented with 145.9 mM sucrose. Histological analysis revealed that the number of parenchymatous cell containing starch grains increased in the tuberous roots. In addition, unlike in non-tuberous root, vascular bundles were scattered inner cortex layer. Thirdly, in order to preserve and stimulate the germination, microtubers were stored at $4^{\circ}C$ refrigerator during 9 months and then transplanted to the artificial soils (vermiculrite : peatmoss = 1:1 v/v), resulting that the rates of survival and germination were 75% and 70%, respectively. These results indicated that mass propagation of C. lanceolata was achieved by in vitro microtuber formation, suggesting that this protocol might be applied for not only the propagation of elite clones but also conservation of C. lanceolata germplasm.

• The korean journal of orthodontics
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• v.34 no.2 s.103
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• pp.143-152
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• 2004

It has not been elucidated whether the initiation of condylar development of the mandible is related with the periosteum of the mandible, or if it derives from a separate programmed blastema not related with the mandible. Also, although the mandibular condylar cartilage is known to promote growth, few studies have dealt with molecular-biologic mechanisms such as the expression of specific genes according to the differentiation of the mandibular condyle. To elucidate the unique cellular characteristics, development, and differentiation process of the mandibular condyle, an examination of expressions of genes characteristic of cartilage and bone were carried out using RT-PCR and mRNA in situ hybridization. 1. Type? collagen mRNA was detected with type II collagen mRNA in the differentiation and growth process of the cartilage of the mandibular condyle. TypeII collagen mRNA was demonstrated in the whole resting md upper part of the poliferative zone, whereas type II collagen mRNA was observed in the resting, proliferative and upper hypertrophic cartilage zone of the mandibular condyle. 2. The condylar cartilage rapidly increased in size due to the accumulation of hypertrophic chondrocytes as characterized by the expression of type II collagen mRNA during postnatal development. 3. BMP-4 mRNA was present in the anlage of the future condylar process and also in the ossifying mandibular body. 4. IHH mRNA was limited exclusively to the lower part of the proliferative zone and the upper part of the hypertrophic cartilage zone during condylar development. These findings were different from those in the growth-plate cartilage of the long bone, indicating a characteristic feature of the differentiation of the chondrocytes in the condylar cartilage present in prenatal and postnatal development. Furthermore, it was also suggested that chondroblasts of condylar cartilage rapidly differentiate into hypertrophic chondrocytes with increased functional Load force such as muscle activity and mastication.

• Journal of agriculture & life science
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• v.50 no.5
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• pp.81-93
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• 2016

Rehmannia glutinosa(Gaertn.) DC. is a herbaceous perennial plant and belonging to the Scrophulariaceae and used as roots for medicinal part and purpose. R. glutinosa is and usually used for fresh rehmannia root or prepared rehmannia root. However, it is very difficult to propagate using the seeds because of lack germination so it is propagated using the vegetative method as the rootstock. Currently, propagation and harvesting using the rootstock of R. glutinosa has difficulties about production of the high quality and quantity in R. glutinosa because of root rot disease. To optimize in vitro cultures and to improve the rootstock and seedling of R. glutinosa after morphological and genetical determination, 5 plant culture media (MS, DJ, LS, QL, and WPM) were used in this study then WPM was selected for better growth, for multiplication condition(WPM + IAA 1.0 mg/L + IBA 0.5 mg/L), and for root enlargement condition(WPM + NAA 0.1 mg/L) of R. glutinosa. Based on these results, in vitro seedlings of R. glutinosa were transferred to soil for acclimation with environment adaptation and shown the positive effects about root enlargement and root formation. Therefore, it can be used for high quality of R. glutinosa production and production of the rootstock based on propagation using in vitro seedlings of R. glutinosa.

• The Journal of the Convergence on Culture Technology
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• v.9 no.1
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• pp.239-248
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• 2023

This study is a descriptive correlation study to identify the relationship among online collaborating learning attitudes, empathy, critical thinking disposition, and sense of community in nursing students in the online learning environment during COVID-19. Data were collected from 129 nursing students. The SPSS/28.0 program was used to analyze the data using descriptive statistics, Pearson's correlation coefficient, independent t-test, one-way ANOVA, Scheffé test, Pearson's correlation analysis, and hierarchical multiple regression. Factors that significantly affect sense of community in nursing students were online collaborating learning attitudes and critical thinking disposition, and the explanatory power was about 42.2%. Based on these results, in order to increase sense of community of nursing students in non-face-to-face learning environment, it is required to strengthen the problem-solving-centered learning method cultivating the online collaborating learning attitude and critical thinking disposition.

• Korean Journal of Medicinal Crop Science
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• v.2 no.3
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• pp.246-250
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• 1994

This study carried out to induce plant regeneration and callus formation from leaflet in MS medium with 2.4-D, NAL and IAA for in vitro growth of tuber, Kinetin and BA were used for plant regeneration. $NH_4NO_3$ and $KNO_3$ as a nitrogen source and $(NH_4)_2SO_4$, as a sulfate source were tested for in vitro growth of tuber. The resutls ars as fellows : 1. For the callus formation from leaflet and differentiation potency of organ, 2.4-D was more effective than IAA in MS medium under $26^{\circ}C$ and light condition of 8 hours a day. 2. For the plant regeneration from callus, MS medium with $2.0\;mg/{\ell}$ BA was most effective under $26^{\circ}C$ and light condition of $16{\sim}24$ hours a day. 3. For the in vitro growth of tuber, $KNO_3$ by $3.0g/{\ell}$ in MS medium was effective. This condition enhanced the growth of tuber 2.5 times compared with that in MS medium with $2.0\;mg/{\ell}$ BA.

• Horticultural Science & Technology
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• v.16 no.3
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• pp.358-360
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• 1998

Series of in vitro experiments in Lilium callosum were conducted to investigate efficient multiplication through finding the optimal cultural environment, and organogenic capability of cultural explants, and then to determine the progressive method for enhancing bulblet growth in Lilium callosum scale culture. Twenty-four hr photoperiod was most effective for the growth of bulblet and the formation of other organs. Optimum light intensity for bulblet growth was 2,500~5,000 Lux. When bulbets were subcultured, growth of bulblets were enhanced by removing excessive leaf blade. Number of bulblets per scale increased as mother scale size increased, whereas diameter of bulblet from the small size mother scale increased. Bulblet formation and development was induced when explants were placed above the medium to be exposed to more light.

• Journal of Plant Biotechnology
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• v.31 no.4
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• pp.301-306
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• 2004

Multiple shoots of garlic (Allium sativum L.) were propagated in bioreactors containing MS medium supplemented with 2% sucrose for 3 weeks. Microbulbs were induced on MS medium supplemented with 0.1mg/L NAA and 11% sucrose for 9 weeks. For multiple shoot proliferation, leaves in the shoot must be removed before cultures. When the multiple shoots were cultured without removal of leaves, more than 90% of hyperhydricity and no microbulb formation were observed. Histological observation also indicated irregular size and shape of the cells in hyperhydricity of the shoot. Microbulbs were strarted to form from the shoot after 7 weeks of culture by protuberance of adventitious shoot buds followed by inner periclinal divisions and simultaneous anticlinical division in the epidermis of meristematic bulge. Analysis of ploidy level indicated no phenotypic variations in both multiple shoots and microbulbs induced from the mother plant, suggesting genetic homogeneity among the regenerants.

• Journal of Bio-Environment Control
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• v.16 no.3
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• pp.174-179
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• 2007

Although the relationship between fermentation and factors such as soil water, redox potential, rootstocks and climatic conditions has been reported, its mechanism of fermentation is still not clear. Transpirations of leaf and fruit at different climatic conditions, influence of soil water potential and atmospheric vapor pressure deficit (VPD) on fermentation were evaluated. Transpiration rate decreased with decreasing soil temperature and soil water potential. Low VPD conditions which occurred during low air temperature and high humidity also decreased transipration rate. These data exhibit that fruit water balance affected by various factors relate to transpiration. Our results also indicate that high hydraulic conductance of root, high soil water potential and low VPD condition exert a significant effect on fermention of oriental melon and so called "water filled fruit".

• The Korean Journal of Quaternary Research
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• v.14 no.2
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• pp.101-107
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• 2000

Using the phytogram system, this study monitored hourly environmental factors(climate and soil), and radial growths and cambium activities of conifers in Worak mountain for 28 months from May 1996 to October 1998 to examine the influences of climatic factors on tree growths/carnbium activities of conifers in Worak Mountain, Korea. The phytogram system first puts a fine electrode into cambial zone. This device can automatically record environmental factors and cambium electrochemistry(hydration and proton levels). Dendrometers are attached to the phytogram for monitoring seasonal dynamics of cambial growth. We compared the results of radial growth by species and by diameter class. The growth decreased in order of Larix leptolepis, Pinus densiflora and Pinus rigida. Pre-monsoon growths were fast and May-June moisture regime was the most critical for all species. In the middle of September, radial growths were finished. The proton level and stem diameter reached the minimum at 4 p.m. On the other hand, the hydration level reached the maximum at 4 p.m. This diurnal change resulted from transpiration and the release of water from phloem storage to sapwood through xylem stream.

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.1010-1014
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• 2009

Acceleration of the globalization process as they are internationally accepted, standardized. A lot of somebody started to feel tired of the standards symbols, and like to pursuit the original and natural, and hope that the new interest in the emergence of visual symbols. Dongba (東巴文字) text are Naxi(納西族) Dongba pictograph (象形文字) of a concrete nature in china, Characterized by simplicity, abstraction, associative, interesting, decorative, symbolic etc. These features can quickly identify and satisfy to the people's demand for special aesthetic.