• Polymer(Korea)
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• v.36 no.3
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• pp.357-363
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• 2012

Surface-modified poly(L-lactic acid) (PLLA) films and scaffolds were treated with plasma discharge in oxygen gas and subsequently subjected to $in$ $situ$ grafting of acrylic acid (AA) in order to increase the cell compatibility. The surface of AA-grafted PLLA was converted to hydroxyapatite (HA)-deposited PLLA in stimulated body fluid (SBF). After the samples were immersed in phosphate-buffered saline (PBS), fetal bovine serum (FBS), normal saline, or cell medium, the water contact angles were significantly reduced on the surface of HA-deposited PLLA. Chondrocyte and osteoblast showed a higher attachment and cell proliferation on HA-deposited surfaces and in particular, it was confirmed that chondrocyte was considerably influenced by HA. However, osteoblast showed better cell proliferation on the surfaces immersed in FBS, cell medium or HA-deposited surface. In addition, the cell proliferation in 3D scaffolds was much higher than that on film type, irrespective of chondrocyte and osteoblast. Therefore, such surface-modified PLLAs are expected to be useful as organic-inorganic hybrid scaffolds in the regeneration of cartilage and bone.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.1
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• pp.84-90
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• 1986

An experiment was conducted to know the effects of planting dates (March 5, 15, and 25 and April 4) and transparent polyethylene (P.E.) film treatments(tunnel, tunnel slit, and mulch) on air and soil temperatures and growth and yield of a sweet corn variety, Great Bell. Maximum air and soil temperatures and minimum air and soil temperatures were greater at tunnel>tunnel slit>mulch in that order. Differences in maximum air and soil temperatures among the P.E. film treatments were much greater than those in minimum air and soil temperatures. However, when film was opened due to high air temperature over 40$^{\circ}C$ in the tunnel, air temperature was similar but soil temperature was lower com-pared to mulch. High temperature stress could be avoided in tunnel slit without opening film by increase in the number of slits. Cold damage of corn seedlings was avoided by tunnel and reduced by tunnel slit, and frost-damaged seedlings under the mulch were recovered in few days. The number of days from planting to silking was reduced as planting date delayed. At early plantings, tunnel enhanced early growth and silking, but it delayed at late plantings because tunnel was opened during the most of day time due to high temperature. Black streaked dwarf virus(BSDV) disease was more severe at early plantings and it was reduced in tunnel slit at late plantings because plants were grown under the film at the time of infection. The number of marketable ears was similar among all treatments except mulch at March 5 planting where BSDV was severely infected. Gross income was high in tunnel and tunnel slit at March 25 planting which had more larger marketbale ears and tunnel and tunnel slit at March 5 planting which had higher market price.

• Journal of Korean Society of Forest Science
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• v.96 no.1
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• pp.83-88
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• 2007

Micropropagation of Ulmus davidiana Planch was established via adventitious shoot formation from the segments of adventitious roots. Adventitious roots were produced directly from root segments of seedlings on a 1/2 SH medium plus various concentrations of IBA. The maximum growth of adventitious roots was observed in the presence of 2.0 mg/L IBA. After the segments of adventitious roots were cultured on various cytokinins (zeatin, 2-iP, BA, kinetin) and cytokinins plus auxin (IBA), formation of adventitious shoot was investigated. Among cytokinin treated, kinetin was the most effective on both adventitious shoot induction and number of shoots. Especially, 2.0 mg/L kinetin was the best to increase adventitious shoot induction (95.8%) and a number of shoots (8.4). Adventitious shoots were rooted on 1/2 WPM medium and the plantlets were acclimated 100% on composed soil (peatmoss : vermiculite 1 : 1).

• Microbiology and Biotechnology Letters
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• v.32 no.2
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• pp.135-141
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• 2004

Human granulocyte colony-stimulating factor (hG-CSF) is a hematopoiesis agent that principally affects the differentiation of neutrophils in the bone marrow. At present, recombinant hG-CSF is used successfully in the treatment of chemotheraphy-induced neutropenia and its indication has been expanded to bone marrow transplantation and aplastic anemia. In this study, we have constructed rhG-CSF secretion plasmid pYRC1 in which OmpA signal sequence/hG-CSF gene was expressed under the control of the T7 promoter. rhG-CSF produced in E. coli BL21 (pYRC1) grown at $37{\circ}C$ was found in aggregates. However, 15% of the periplasmic protein was soluble rhG-CSF when the E. coli BL21 (pYRC1) was cultured at $25^{\circ}C$ for 7 h in the modified MBL medium containing 10 g/$\ell$ glucose with 10 $\mu$M IPTG induction. The production of soluble rhG-CSF in E. coli BL21 (pYRC1) using fed batch culture was also studied. In the fed batch culture system, the final yield of rhG-CSF produced from E. coli BL21 (pYRC1) was increased from 4.4 mg/$\ell$to 24 mg/$\ell$by controlling the specific growth rate from $0.43 h^{-1}$ to $0.14 h^{-1}$, and optimizing the time of induction.

• Journal of Korean Society of Forest Science
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• v.96 no.6
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• pp.639-643
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• 2007

The use of forest biomass resources produced by forest tending and residual forest biomass that was not gathered on commercial thinning or cutting area was estimated to be come into the spotlight as bioenergy sources in these days of new high oil price. With considering these problems, This study was investigated about possibility with biomass calculation and convertibility to fossil fuel in these area. Total forest tending area in the year 2005 was 294, 115 ha and the yield gathered from these area was $143,747m^3$. It is equivalent to biomass of 115,000 ton and caloric value of 533,199Gcal. However, the potential and additional yield that is residual in forest stands was 2,483,000 ton. It is equivalent to 11,133 billion won of oil which is 20 times of the actual yield produced by forest tending. Therefore, these amount of biomass has a substitution effect of the fossil fuel. Moreover, the residual biomass that is not gathered at commercial thinning and cutting area was 475,000 ton. It is equivalent to 2,206,235 Gcal of heating value and about 2,211 billion won of oil. This potential amount could be a new energy source to be a substitution effect of fossil fuel. It is time to be interested in the forest biomass as a renewable and environment-friendly resource and its substitution effect of fossil fuel.

• Korean Journal of Medicinal Crop Science
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• v.14 no.4
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• pp.255-260
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• 2006

Culture conditions for high frequency plant regeneration via somatic embryogenesis from embryogenic cell suspension cultures of Hovenia dulcis are described. Germinated somatic embryos were selected for induction of secondary embryogenesis. Friable embryogenic cells were induced directly from somatic embryos when transfer to 1/3 MS solid or liquid medium lacking plant growth regulators. The temperature strongly effected on induction of secondary embryognesis than other conditions in culture. All somatic embryos produced friable embryogenic cell clumps within 10 days when germinated somatic embryos cultured in 1/3 MS medium at $30^{\circ}C$ in suspension culture. No somatic embryos formed from embryogenic cell suspension cultures at $18^{\circ}C$. Numerous somatic embryos were induced and subsequently developed uniformly into germination stage from suspended cell clumps after 4 weeks of culture on $18^{\circ}C$. Plantlets conversion were observed on $18^{\circ}C$ when germinated somatic embryos were transferred to 1/3 MS solid medium without plant growth regulators or supplemented with 0.1-0.5 mg/l benzyladenine.

• Journal of Periodontal and Implant Science
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• v.30 no.2
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• pp.287-305
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• 2000

The purpose of this study is to evaluate the effects of bioresorbable membranes in guided bone regeneration of streptozotocin induced diabetic rats. 50 Sprague-Dawley rats were randomly categorized into 4 groups: Group 1 & 2 had 10 normal rats each and group 3 & 4 included 15 streptozotocin induced diabetic rats each. Defect measuring 7mm in diameter was formed on every rat calvarium. No membrane was used in groups 1 & 3 and membranes were used in groups 2 & 4. The rates were sacrificed at 2 and 4 weeks after defect formation. Routine histological specimens were prepared. Masson-trichrome and HE stain were done before light microscopy. Guided regenerative potential was evaluated by measuring the amount of new bone formation in the calvarial defect by histomorphometry. Following results were obtained. 1. New bone formation in the diabetic groups was significantly less that than in the normal groups regardless of membrane use(p<0.05). 2. In the comparison of new bone formation in the normal groups, membrane group showed significantly more bone formation(p<0.1). 3. When the amount of new bone formation was compared in the diabetic groups, more bone was formed in the membrane groups but the difference was not statistically significant.4. In the normal groups the amount of new bone formation was significantly greater at 4 weeks compared to that at2 weeks(p<0.05) but amount of bone regeneration at 4 weeks was not significantly greater than that at 2 weeks in both diabetic groups.

• Korean Chemical Engineering Research
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• v.43 no.1
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• pp.140-145
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• 2005

The desulfurization abilities using GC/microreactor have been examined for $CuO-Fe_2O_3$ sorbents with respect to calcination temperatures of 700, 900 and $1,100^{\circ}C$. CuO was used as a main active component, $Fe_2O_3$ was used as an additive one and 25 wt% $SiO_2$ was used as a support. The desulfurization reaction temperature was $500^{\circ}C$ and the regeneration reaction temperature was $700^{\circ}C$. From the XRD results, the $CuFeO_2$ compound has been observed for the fresh sorbent calcined at $1,100^{\circ}C$ and the $CuFeS_2$ compound for the reacted sorbent calcined at $1,100^{\circ}C$. By the BET results, however any significant differences among sorbents calcined at the three different temperatures of 700, 900 and $1,100^{\circ}C$ haven't been observed. Especially CFS1 (CuO : $Fe_2O_3$ : $SiO_2$=67.5 wt% : 7.5 wt% : 25 wt%) sorbent calcined at $1,100^{\circ}C$ maintained about 10 g sulfur/100 g sorbent for 100 cycles by the cyclic test.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.44 no.1
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• pp.95-101
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• 2018

The epidermis which is stratified by epithelial tissue renewal based on keratinocyte differentiation protects the organism from various environmental insults by forming a physical barrier. Autophagy is a mechanism which mediates lysosomal delivery and degradation of protein aggregates, damaged organelles and intracellular microorganisms. Recent reports have shown that autophagy has critical roles for proper terminal differentiation to stratum corneum via removing metabolic organelles and nuclei. However, whether increasing autophagy can activate epidermal differentiation is unknown. Here, we screened a library of natural single compounds and discovered that betaine specifically increased the LC3 positive cytosolic punctate vesicles and LC3-I to LC3-II conversion in HaCaT human keratinocyte cell line, indicating increased autophagy flux. mTOR pathway, which negatively regulates autophagy, was not affected by betaine treatment, suggesting betaine-induced autophagy through an mTOR-independent pathway. Betaine-induced autophagy was also observed in primary human keratinocyte and skin equivalent. Furthermore, epidermal thickness was increased in skin equivalent under betaine treatment. Overall, our finding suggests that betaine as a novel regulator of autophagy may induce epidermal turnover and improve the skin barrier abnormality of the aged epidermis.

• The Journal of the Convergence on Culture Technology
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• v.6 no.4
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• pp.385-389
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• 2020

The medical drama has developed into a story centered on 'people', raising viewers' sympathy. The story of the drama is the true life story of doctors, patients and families. It is also a story that reminds me of 'a little special day of our ordinary people'. And the song played and sung by five characters in the drama became a factor that stimulates nostalgia and increases immersion. The highest viewer rating was 14.1%, and 51,584 blogs alone were registered. According to the big data analysis, the related words were 'Wise OST', 'Album Name', 'Artist Name', 'Two Hours in a row', 'Record', 'Remake', 'OST Revealed', 'Advertisement Revenue', 'Playlist', 'Aroha' and 'Cho Jung-seok'. The commercialization of medical dramas includes 'Sales of Drama OST Albums', 'Organizing Online Live Concerts (PPL in Advertising)', 'Publishing Piano Music', 'Picture of People-Oriented Photography', 'Making Music Video Editing Drama Highlight', 'YouTube Upload Profits', 'Mask' and 'Disinfectant'. it is predicted that the touching story of Corona 19 and the charming humanity will unfold. The limitations of the research will require analysis of various works by genre and attempts to analyze consumer values by industry.