• Korean journal of communication and information
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• v.35
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• pp.211-249
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• 2006

This study investigated how many and which articles readers read in daily newspapers. Distinguished from previous research that measured readers' perception of their reading habits, this study picked up readers who read the newspaper in the morning, showed them every article in the newspaper, and asked them whether they read each article. This method enhanced the accuracy of measuring subjects‘ reading behavior. According to the results, 6.2% of the readers read at least half of the articles of the general section in the newspaper. Fewer readers went over the economic section of the newspaper. It was 4.1% of the readers. There were only 1.1% of readers who did not read any article of the general section, but the rate soared to 26.5% for the economic section. Many newspaper readers did not skip the first five pages of the newspaper, however the highest readership pages were found in the national coverage located in the middle of the general section. On the other hand, few readers read the articles on pages covering culture, international issues, and people. Readership of the top stories showed some unexpected results. The top stories of national coverage located in the middle of the general section were read by more readers than the top stories of the front pages. This study also investigated the difference between young and old readers. The readers of twenties and thirties did not read as many top stories on major pages and editorials as the readers of forties and older.

• Journal of Aquaculture
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• v.19 no.4
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• pp.310-314
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• 2006

This study was carried out to investigate grazing of brackish water cyclopoid copepod Paracyclopina nana on four microalgae species (Tetraselmis suecica, Isochrysis galbana, Phaeodactylum tricornutum and Dunaliella tertiolecta) and different food concentrations raging from 5 to 55 ng chl a/ml. The grazing of P. nana was examined by the analysis of decreased number of microalgae and chlorophyll a content in rearing water and pigment content in the gut of P. nana. The maximum content of decreased chlorophyll a and gut pigment in P. nana varied with microalgae species and concentrations. It appeared at the food concentration 30 ng chl a/ml in T. suecica, 40 ng chl a/ml in I. galnaba and D. tertiolecta, and 45 ng chl a/ml in P. tricornutum, respectively. The grazing rate of a P. nana per hour also varied with different microalgae species and concentrations. The maximum grazing rate per hour of P. nana fed T. suecica with 39.3 ng chl a/ml was the highest with 0.63 ng chl a/h, but lowest with 0.52 ng chl a/h. From these results, it can be concluded that T. suecica is the best species among four microalgae species for the mass culture of P. nana and daily optimum food concentration of P. nana is $25{\sim}39$ ng chl a (approximately $10{\sim}15{\times}10^4$ cells).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.70-77
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• 2020

Microalgae are independent organisms that perform photosynthesis and can alter the culture environment to increase accumulation of useful substances derived from microalgae. In this study, cell growth was measured by incubation for 39 days using MBBM, Neo medium, and seven light sources, which is the main factor affecting cell growth of microalgae S. obliquus. In the case of S. oliquus, which grew in MBBM and Neo medium, cell growth was highest under fluorescent light sources and Red2 LED (R660) light sources, and cell growth was lowest under Infra Red LED (R741) light sources. The average cell growth rate was 17.7% for MBBM and 15.4% for Neo. Comparing the effects of dry cell weight of Neo medium containing nutrients on the production of aquatic plants, MBBM and dry cell weight of Neo resulted in higher cell growth than Neo medium under all LED light sources except for Blue LED (B450). This proves that MBBM is more suitable for increasing the cell growth of microalgae than Neo medium and confirms that light source selection is important in the production of useful materials through mass cultivation of microalgae in the future.

• Journal of Plant Biotechnology
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• v.32 no.1
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• pp.31-35
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• 2005

To obtain regeneration system of onion, we analyzed the effects of 2,4-D and BA concentration on the embryogenic callus induction from mature embryos. The highest embryogenic callus induction ratio was shown on MS medium (Murashie and Skoog 1962) containing $2.5\;\cal{mg/L}\;or\;5\;\cal{mg/L}$ picloram after mature embryos were placed on medium. When induced callus were cultured on half strength of MS medium containing $1\;\cal{mg/L}$ Kinetin, the highest shoot formation ratio was observed on MS medium containing $1\;{mg/L}$ 2,4-D and $1\;{mg/L}$ BA. Embryogenic callus were cultured in MS liquid medium containing $1\;\ccal{mg/L}$ of 2,4-D and $1\;\cal{mg/L}$ BA. The suspension cultured cell clumps could be mass propagated. Embryogenic callus were friable, but non-embryogenic callus included a lot of moisture, hence the identification between embryogenic and non-embryogenic callus as easily achieved. When embryogenic callus as cultured on half strength of MS medium containing $1\;\cal{mg/L}$ Kinetin, shoots were induced. The whole plantlet was obtained on rooting medium containing $0.5\;\cal{mg/}$ of NAA.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.1
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• pp.8-14
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• 2005

Mass culturing of two beneficial organisms used as biofertilizers for crops would reduce the risks in production and minimize the capital involved and this demands appropriate media that supports both organism and also selection of organisms that are not antagonistic to each other. A study was initiated to culture a nitrogen fixer (Rhizobium) and phosphate solubilizer (Bacillus megaterium) in a single medium and to study their growth patterns and shelf life in carrier. The growth of Rhizobium and Bacillus megaterium was assessed in different media and a slight modification in the traditional yeast extract mannitol media promoted the growth of both the organisms. The growth of the individual organisms in the modified medium was assessed by estimating the population at regular intervals and compared to their original medium. Maximum population of Rhizobium and phosphobacteria was at 60 hr when the phosphiobacteria inoculation of later was after 48 hr of Rhizobium inoculation. The shelf life of the individual inoculants in the inoculant containing both the organism in a sterile carrier base revealed no significant differences compared to individual organisms inoculated in a sterilized carrier. The population of both organisms in carrier based mixed inoculant remained at $10^8$ cells till 90 days.

• Development and Reproduction
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• v.14 no.4
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• pp.233-241
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• 2010

Human adipose stem cells are an abundant, readily available population of multipotent progenitor cells that reside in adipose tissue and these cells have characteristics very similar to bone marrow mesenchymal stromal cells (BMMSCs). However, liposuction procedure, donor age, body mass index, and harvesting sites might generate differences in the initial cell population and the preparations are a heterogeneous mixture of precursors with different subsets. Therefore, in this study, we investigated the characteristics of human thigh adipose stem cells and the differentiation potential into mesodermal and endodermal lineage. Thigh adipose stem cells maintained fibroblast-like morphology similar to BM-MSCs and they underwent average 56.5 doublings and produced $5{\times}10^{22}$ cells. These cells expressed SCF, Oct4, nanog, vimentin, CK18, FGF5, NCAM, Pax6, BMP4, HNF4a, nestin, GATA4, HLA-ABC, and HLA-DR genes at p3 and they also expressed Oct4, Thy-1, FSP, vWF, vimentin, desmin, CK18, CD54, CD4, CD106, CD31, a-SMA, HLA-ABC proteins. Moreover, they could differentiate into mesodermal lineage cells such as adipocyte, osteoblast and chondrocyte. In addition, they also differentiated into insulin secreting cells in our culture condition. In conclusion, human thigh adipose stem cells retain proliferative potential and expression patterns similar to BM-MSCs and they also differentiate into various cell types. Thus, human thigh adipose stem cells might be useful alternative cell source for clinical application.

• Microbiology and Biotechnology Letters
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• v.44 no.4
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• pp.522-528
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• 2016

In this study, we investigated the possibility of using hydrolysates of lignocellulosics (rapeseed straw, barley straw, rice straw) and marine macro-algae (Undaria pinnatifida, Laminaria japonica, Enteromorpha intestinalis, and Gracilaria verrucosa) to cultivate Chlorella saccharophila. The growth of C. saccharophila was inhibited by 7 hydrolysates without active carbon treatment. In contrast, hydrolysates treated with active carbon increased the cell growth and product (oil and chlorophyll) formation by C. saccharophila. The oil contents of C. saccharophila treated with each hydrolysate were $41.26{\pm}0.69%$ (glucose), $22.06{\pm}1.21%$ (rapeseed straw), $28.65{\pm}1.08%$ (barley straw), $31.15{\pm}0.76%$ (rice straw), $31.50{\pm}2.12%$ (U. pinnatifida), $31.49{\pm}4.53%$ (L. japonica), $29.63{\pm}3.93%$ (E. intestinalis), and $26.15{\pm}1.99%$ (G. verrucosa), respectively. Lignocellulosics and marine macro-algae may be useful resources for improving the mass cultivation of C. saccharophila.

• Applied Biological Chemistry
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• v.24 no.2
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• pp.105-111
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• 1981

Growth responses of Brevibadterium ammoniagenes BA 17-2, which had been obtained by the treatment of several mutagens in our previous report, were investigated to select the preliminary optimal concentrations of phosphate, $Mg^{++}$, $Mn^{++}$ and thiamine for the production of 5'-XMP aminase. In this experiment it was shown that the concentration of phosphate in the medium has an important effect on the growth of microorganism. Using the medium containing 0.2% of $MgSO_4{\cdot}7H_2O$, 3mg/l of $MnSO_4{\cdot}H_2O$and $1\;mg/l$ of thiamine-HCl, the maximum cell mass was obtained at the concentration of 0.4% of $KH_2PO_4$ and $K_2HPO_4$, respectively. Above the concentration of these phosphates, cell growth was inhibited as the phosphate concentration increased to 1%, but the inhibition was overcome by the addition of 1% of $MgSO_4{\cdot}7H_2O$ and 3mg/l of thiamine-HCl. The 5'-XMP aminase activity was also influenced by the concentration of phosphate, $Mg^{++}$, $Mn^{++}$, and thiamine. In addition, the optimal culture pH and temperature for the enzyme activity were found to be 6.8 and $32^{\circ}C$, respectively.

• Applied Biological Chemistry
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• v.46 no.4
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• pp.285-290
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• 2003

This study was conducted to select the bacteriocin-producing microoreanism cultivated in the rice bran culture and to characterize the produced bacteriocin for the further purpose of economical and anti-bacterial rice bran protein film. Pseudomonas putida 21025 was cultivated from rice bran and identified as a producer of a bacteriocin which showed bactericidal activity against Pseudomonas aeruginosa 9027. Bacteriocin produced by Pseudomonas putida 21025 showed a broad spectrum of activity against spoilage and soil bacteria. The activity of the bacteriocin produced by Pseudomonas putida 21025 decreased after 1 hr of staying at the temperature of $50^{\circ}C$, and with the presence of some organic solvents, except hexane and ethanol. However, the bacteriocin activity was stable throughout the pH ranges of 6-9 for 2 hrs, at the temperature lower than $50^{\circ}C$, and with the presence of ethanol for 3 hrs. The bacteriocin was partially purified by 50% ammonium sulfate precipitation followed by subsequent dialysis. Direct detection of the partially purified bacteriocin on SDS-PAGE suggested that it had an apparent molecular mass of about 21.6 kDa.

• Archives of design research
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• v.20 no.1 s.69
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• pp.167-176
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• 2007

As much time is being spent with the family at weekends by the development of leisure culture, many people have begun to enjoy camping in the field. While many people use pensions or camping cars, many families or groups of friends go on camping in the summer holiday season. Although the tent design in this country has gradually been developed, it is not as developed as overseas designs with unique design characteristics according to climate, cultural behavior and colors. In this research, the American and Korea tent designs are compared in terms of color and frame. The differences are analyzed and a direction for tent designs appropriate for Korea in terms of size, area, ease of carriage and installation is proposed through theoretical data and idea sketches. The frame weight has been minimized and the durability increased for the ease of carriage and installation. The style and number of windows have been increased in order to provide a comfortable space by understanding the influx of airflow and the size of the tent has also been increased to provide extra space for storage. The information on the overseas and domestic tent design trends led to a color comparison and the extraction of images of language. The tent based on the new design is currently being mass-produced in China following 3 months of preparation including sample making and testing.