• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.251-254
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• 2011

Botrytis cinerea infects stems and leaves of greenhouse tomatoes and can cause serious economic losses. This study was conducted to develop environment-friendly control method against tomato gray mold. Antagonistic microorganisms (bacteria) were screened for control activity against Botrytis cinerea, both in vitro and in vivo, using stem sections. One hundred bacterial strains were isolated from the rhizospheric soil of various plants including tomato. These strains were screened for growth inhibition of Botrytis cinerea on agar plate by the dual culture and thirty strains showing strongly inhibitory effect against the pathogen were selected first. Among thirty strains, JB 5-12, JB 22-2, JB 22-3, U 4-8 and U46-6 reduced significantly disease incidence, when applied simultaneously with the pathogen. These results suggested that five antagonistic bacteria strains selected have the potential to control tomato gray mold in organic farming.

• Journal of Plant Biology
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• v.30 no.3
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• pp.205-213
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• 1987

Soybean, inoculated with effective Rhizobium japonicum 110, were grown by sand culture with nutrient solution containing either of 0, 1, 3, 10 or 30mM NO3-/l, and analyzed growth characteristics, NR activity, N2-fixation activity, and changes of ureide contents during the growing period. The amount of nodule formation decreased abruptly by nitrate treatment, the maximum nodule dry weight was 1.59, 1.05, 0.78, 0.09 and 0.008 g plant-1, respectively for each treatment on the 98th day. Specfic activity of N2-fixation showed the maximum rates of 140, 101, 37, 5 and 2.2 nM dw.mg-1.hr-1, respectively for each treatment in the earlier growth period. The maximum acetylene reduction activity on the 98th day after sowing was 81.5, 35.3, 14.3, 0.1 and 0.0045 $\mu$M C2H4 plant-1.hr-1, respectively for 0, 1, 3, 10 and 30 mM of NO3- gradients. Nitrate reduction activity increased along with nitrate gradients, and decreased abruptly with age. Relative abundance of ureides in plant organs was high in reproductive growth, and showed the maximum value in fully symbiotic dependent plant. Relative abundance of ureides in stem is a useful indication for the evaluation of nitrogen fixation in nodules of symbiotic plant.

• International Journal of Contents
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• v.15 no.2
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• pp.53-58
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• 2019

The aim of this paper is to discuss how designers lead and direct 'technology-driven society' using their creative communication skill. To this end, it is required for communication designers to take conscious steps to recognize the future direction of their profession. Despite the advancement in technology, there is a human being at the center of all design activities. From a certain point of view, contemporary communication design takes an open-ended exploration of the subject matter, rather than a finished output. The notion of creative leadership may potentially expand more in terms of improving the methodology of today's visual culture. The paper will examine creative leadership that could be proposed by the challenge of discourse upon the upcoming industrial revolution. Today, communication designers are confronted by new leadership opportunities and challenges. Some leading designers seem to focus on brand new media technologies to prepare the 4th industrial revolutions. However, communication design cannot be discussed in the medium but can be understood as a process. Top-down and bottom-up process is always a concerned about the relationship since the focus of leadership has changed. In the top-down process, the leadership has existed between 'designer and client' because designers have played their role as a problem solver. On the other hand, there is a different model of leadership between 'design and technology' based on bottom-up process, which stem from the design authorship. In this regard, the new definition of creative leadership in the $4^{th}$ industrial revolution proposes a designer as a problem-finder based on the relationship between the 'designer and the public'.

• Restorative Dentistry and Endodontics
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• v.45 no.4
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• pp.52.1-52.11
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• 2020

Objectives: Yttria-stabilized tetragonal phase zirconia has been used as a dental restorative material for over a decade. While it is still the strongest and toughest ceramic, its translucency remains as a significant drawback. To overcome this, stabilizing the translucency zirconia to a significant cubic crystalline phase by increasing the yttria content to more than 8 mol% (8YTZP). However, the biocompatibility of a high amount of yttria is still an important topic that needs to be investigated. Materials and Methods: Commercially available 8YTZP plates were used. To enhance cell adhesion, proliferation, and differentiation, the surface of the 8YTZP is sequentially polished with a SiC-coated abrasive paper and surface coating with type I collagen. Fibroblast-like cells L929 used for cell adherence and cell proliferation analysis, and mouse bone marrow-derived mesenchymal stem cells (BMSC) used for cell differentiation analysis. Results: The results revealed that all samples, regardless of the surface treatment, are hydrophilic and showed a strong affinity for water. Even the cell culture results indicate that simple surface polishing and coating can affect cellular behavior by enhancing cell adhesion and proliferation. Both L929 cells and BMSC were nicely adhered to and proliferated in all conditions. Conclusions: The results demonstrate the biocompatibility of the cubic phase zirconia with 8 mol% yttria and suggest that yttria with a higher zirconia content are not toxic to the cells, support a strong adhesion of cells on their surfaces, and promote cell proliferation and differentiation. All these confirm its potential use in tissue engineering.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.29 no.4
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• pp.279-288
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• 2007

In the present study, we focused on stem cells in the dental papilla of the tooth germ. The tooth germ, sometimes called the tooth bud, is the primordial structure from which a tooth is formed. The tooth germ consists of the enamel organ, the dental papilla, and the dental follicle. The dental papilla lies below a cellular aggregation of the enamel organ. Mesenchymal cells within the dental papilla are responsible for formation of dentin and pulp of a tooth. Tooth germ disappears as a tooth is formed, but that of a third molar stays in the jawbone of a human until the age of 10 to 16, because third molars grow slowly. Impacted third molar tooth germs from young adults are sometimes extracted for orthodontic treatment. In the present study, we evaluated the osteogenic activity and mineralization of cultured human dental papilla-derived cells. Dental papillas were harvested from mandible during surgical extraction of lower impacted third molar from 3 patients aged 13-15 years. After passage 3, the dental papilla-derived cells were trypsinized and subsequently suspended in the osteogenic induction DMEM medium supplemented with 10% fetal bovine serum, 50 g/ml L-ascorbic acid 2-phosphate, 10 nM dexamethasone and 10 mM -glycerophosphate at a density of $1\;{\times}10^6\;cells/dish$ in a 100-mm culture dish. The dental papilla-derived cells were then cultured for 6 weeks and the medium was changes every 3 days during the incubation period. Dental papilla-derived cells showed positive alkaline phosphatase (ALP) staining during 42 days of culture period. The formation of ALP stain showed its maximal manifestation at day 7 of culture period, then decreased in intensity during the culture period. ALP mRNA level was largely elevated at 1 weeks and gradually decreased with culture time. Osteocalcin mRNA expression appeared at day 14 in culture, after that its expression continuously increased in a time-dependent manner up to day 28. The expression remained constant thereafter. Runx2 expression appeared at day 7 with no detection thereafter. Von Kossa-positive mineralization nodules were first present at day 14 in culture followed by an increased number of positive nodules during the entire duration of the culture period. Osteocalcin secretion was detectable in the culture medium from 1 week. The secretion of osteocalcin from dental papilla-derived cells into the medium greatly increased after 3 weeks although it showed a shallow increase by then. In conclusion, our study showed that cultured human dental papilla-derived cells differentiated into active osteoblastic cells that were involved in synthesis of bone matrix and the subsequent mineralization of the matrix.

• Journal of the Korean Applied Science and Technology
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• v.33 no.4
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• pp.627-633
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• 2016

Sweet sorghum [Sorghum bicolor (L)] is one of the major crops for biofuels such as sugarcane and sugar beet which raw materials rich in saccharide. Sweet sorghum juice was extracted from the stem. It's composed of fermentable sugars such as glucose, fructose and sucrose. Ethanol from the extracted sweet sorghum juice can be easily produced by yeast fermentation process. Sweet sorghum juice is consisted of not only sugars but also various nutrients like nitrogen and phosphate. For commercial production of bioethanol, seed culture is one of the important parts of fermentation, so that optimal culture medium should be selected for the reduction of processing costs. In this study, sweet sorghum juice was estimated as a culture medium for seed culture of cellulosic bioethanol. For the comparison of cultures with various substrates, it used YPD including each 5 g/L yeast extract and peptone, sweet sorghum juice and hydrolyzed Miscanthus was taken part in the culture with 2%, 5% and 10% sugar conditions. Based on media of YPD and sweet sorghum juice, cell-mass concentration was obtained maximum more than $2.5{\times}10^8CFU/mL$ after 24 h of cultivation. Consequently sweet sorghum juice is suitable for the cell culture with more than $1.0{\times}10^8CFU/mL$ after 12 h of cultivation. This can be used as a culture medium for the cellulosic bioethanol industry.

• IMMUNE NETWORK
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• v.1 no.1
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• pp.87-94
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• 2001

Background: Cytokine-mediated ex vivo expansion has been proposed as a means of increasing the number of cord blood (CB) hematopoietic stem cells for transplantation. As well as stem cell number, stromal cells are necessary for functional maturation of hematopoiesis. The purpose of this study was to analyze the development of stromal cells during ex vivo expansion of CB $CD34^+$ cells. Methods : $CD34^+$ cells were purified from CB by magnetic bead selection. The levels of of interleukin-3, interleukin-$1{\beta}$, interleukin-6, granulocyte macrophagecolony stimulating factor and tumor necrosis factor-${\alpha}$ were measured in culture supernatants on 0, 1, 2, and 3 weeks, using ELISA techniques. CB $CD34^+$ cells were expanded in Iscoves modified Dulbeccos medium in the presence of several cytokines. The expression of E-selectin, vascular cell adhesion molecule-1, intercellular adhesion molecule-1, platelet/endothelial cell adhesion molecule-1, von Willebrand factor, vimentin, and CD14 in newly developed stromal cells was examined by immunocytochemical method. Relevant extracellular matrix (ECM) proteins and proper cytokines were also assayed for the most suitable condition for expansion of stromal cells. Results: Several cytokines were found to have been produced by CB $CD34^+$ cells as well as bone marrow-derived $CD34^+$ cells. During ex vivo expansion of CB $CD34^+$ cells, stromal cells appeared in the culture by day 4 and expanded over the following 7-10 days before being confluent by day 2 1. These cells expressed surface markers characteristic of cells of endothelial lineage. Furthermore, these stroaml cells also expanded effectively when treated with thrombopoietin+flt-3 ligand+stem cell factor+leukemia inhibitory factor or 0.1% poly-L-lysine-coated wells. Conclusion: Stromal cells were developed during ex vivo expansion of CB $CD34^+$ cells and that this development could be enhanced further by treating the stromal cells with cytokines or ECM.

• Journal of Bio-Environment Control
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• v.26 no.1
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• pp.1-6
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• 2017

The paprika has emerged as one of the highest-income crops by increase in dimestic and export demand in the greenhouse crops. Nevertheless, there is no standard for fertigation in soil, because general culture system is soilless culture. This study was conducted to establish the optimum nitrogen and potassium application level for paprika fertigation. Four different levels of nitrogen and potassium were applied, treatment levels were 0.5, 1.0, 1.5, 2.0 times of pimiento fertilization recommendations based on soil testing. Experiment to instigate the optimum amounts of nitrogen and potassium were carried out in 2012 and 2013, respectively13. Nitrogen application : stem diameter of 0.5 times was significantly lower than other treatments, but stem length was not affected by nitrogen fiertigation levels. Number of fruit and yield of first fruiting group harvest were not significant difference. but those of the second fruiting group were decreased by increasing nitrogen level beyond 1.0 times treatment and were the lowest in 0.5 times treatment. Overall, the optimum level of nitrogen for fertigation was judged 1.0 times of pimiento fertilization recommendations based on soil testing. Potassium application : Growth was no signigicant trend except stem length. Number of locule, fresh thickness and sugar content were not significant difference. Number of fruit and yield were not significant difference at the first and second fruiting group harvest. But those were significant difference at third fruiting group harvest, maximum yield was obtained by 1.5 times fertigation level. The optimum level of potassium for fertigation was judged 1.5 times of pimiento fertilization recommendations based on soil testing.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.4
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• pp.400-407
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• 1989

This experiment was carried out to study the effects of nitrogen concentration of cultural solution, Rhizobium inoculation, and planting density on the growth and yield of soybean cultivars, Hwanggeumkong, Jangbaegkong, Paldalkong, Clark, and non-nodulation isoline of Clark. Rhizobium inoculation increased the stem length, particularly in Hwanggeumkong, Jangbaegkong, and decreased it significantly in non-nodulation Clark. Stem length was increased by the increase in nitrogen fertilization by the 195ppm level and decreased by the increase in plant population density. Rhizobium inoculation also increased the shoot dry weight, but significantly decreased it in non-nodulation Clark. As nitrogen concentration in the cultural solution increased the shoot dry weight decreased in Jangbaegkong and paldalkong. However, the shoot dry weight was decreased by the increase in plant population density. Rhizobium inoculation and the increase in nitrogen concentration of cultural solution increased the ratio of shoot dry weight to root weight. The Rhizobium inoculation and the increase in nitrogen concentration of cultural solution increased the grain yield per pot in Hwanggeumkong and paldolkong, While non-nodulating Clark showed significant decrease in grain yield. Grain yield per pot was also increased by the increase of plant population density. Grain yield was significantly correlated with shoot dry weight, nodule number, and nitrogen content of the soybean plants. The correlation between nitrogen contents of the soybean plants and stem length, shoot dry weight, and nodulation was significant. The allantoin-N content in stem was also significantly correlated with nodulation.

• Korean Journal of Plant Tissue Culture
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• v.28 no.1
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• pp.7-13
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• 2001

Calli were induced from diploid and haploid tobacco after 4 weeks and maintained on MS medium with combination of 2.0 mg/L 2,4-D,0.1 mg/L BAP and 2.0 mg/L kinetin. Suspension cells were screened through 65 $\mu$m-nylon mesh and 100 $\mu$m-mesh, then they were smeared on selection medium combined with cadmium and PFP by using the low melting agarose of 0.8%. After 30days smeared cultures of the medium the cell was treated with 500 $\mu$M and 1000 $\mu$M to select the resistant cell line were selected. Plant regeneration was induced from the selected cell lines on medium with 0.5, 1.5, 2.0 mg/L BAP and on media with combination of auxin and BAP under 500 $\mu$M and 1000 $\mu$M cadmium. At this time, plant regeneration was achived on cadmium free medium. In case of haploid, occurred from the cell line which is selected in medium with cadmium and PFP. In case of diploid regeneration occurred is in the medium with cadmium alone. The plantlet regenerated from cadmium resistant calli grew well in cadmium 500 $\mu$M. Protein pattern of leaf, root, stem of regenerated plants was analyzed. The quantum was 6.5188 ug/mg.fr.wt in the leaf of plant, 5.3611 ug/mg.fr.wt in the stem, 3.0213 ug/mg.fr.wt in the root. On the other hand, 5.9652 ug/mg.fr.wt. in the leaf of control, 3.5974 ug/mg.fr.wt in the stem of the control, 4.3766 ug/mg.fr.wt. in the root of the control. The one dimension bends regenerated from cadmium resistant calli resistant to cadmium in leaf were 49 involving 198.7KD etc. Disappeared were 4 involving 160.5KD etc, The protein bends were combinized were 3 involving 83.4KD etc. The bends resistant to cadmium stress in stem were 41 involving 4.3KD etc. Disappeared were 5 involving 114.8KD etc. The protein bends combinized were 6 involving 128.7KD etc. The bends which had the resistance to cadmium stress in root is 27 in volving 166,9KD etc. The bends which disappeared were 198.7KD etc. There were 5 involving 83.4KD etc.