• The Korean Journal of Pharmacology
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• v.14 no.1_2
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• pp.1-11
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• 1978

The $Na^+$-and $K^+$-induced $Ca^{++}$ release was measured isotopically by Milipore filter technique in mitochondria isolated from rabbit ventricles. The release of $Ca^{++}$ from mitochondria could be induced by 1-3 mM of $Na^+$ added in incubating medium under the presence of 0.5mM EGTA to prevent the released $Ca^{++}$ from rebinding with mitochondrial membrane. The amount of $Ca^{++}$ released was increased by increasing the concentration of $Na^+$ added. 100mM $K^+$, in itself, did not induce the $Ca^{++}$ release from cardiac mitochondria, the $Na^+$-induced $Ca^{++}$ release, however, was potentiated by the presence of $K^+$. The potentiation of $Na^+$-induced $Ca^{++}$ release by $K^+$ was proportional to the $Na^+/K^+$ ratio presented in the incubating medium. Among the monovalent cations other than $Na^+$, the release of $Ca^{++}$ from cardiac mitochondria was shared only by $Li^+$. The $Na^+$-induced $Ca^{++}$ release could be also observed in the mitochondria isolated from liver and kidney. However, the $Na^+$ sensitivity was somewhat lower in liver and kidney mitochondria than in heart mitochondria. The release of $Ca^{++}$ induced by $Na^+$ in the mitochondria isolated from the experimentally produced failured heart was not different from that in the normal heart mitochondria, and was not directly modified by $10^{-6}{\sim}10^{-5}$ M of Ouabain. From the experiments, it was suggested that the $Ca^{++}$ released from mitochondria by $Na^+$ could be used in excitation-contraction coupling process to initiate the contraction of the cardiac myofibrils. Futhermore, it appeared that the phenomenon of $Ca^{++}$ release from cardiac mitochondria by $Na^+$ and $K^+$ might be related to the inotropic effect of digitalis glycoside which could bring about the increase of $Na^+$ or the reduction of $K^+$ intracellulary through the inhibition of $Na^+$, $K^+$-ATPase.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.3
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• pp.377-384
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• 2012

This study was carried out to evaluate effect of temperature condition on nitrogen mineralization of organic matter, distribution of microbial group by PLFA profiles, and soil microbial community in non-volcanic ash soil. Dried soil 30 g mixed well each 2 g of pellet (OFPE) organic fertilizers, pig manure compost (PMC), and food waste compost (FWC). And then had incubated at $10^{\circ}C$, $20^{\circ}C$, and $30^{\circ}C$, respectively. Nitrogen mineralization rate increased with increasing temperature and that was in the order of FWC>OFPE>PMC. Distribution ratio of microbial group by PLFA profiles showed that was different significantly according to incubation temperature and the type of organic matter. As incubating time passed, density of microbial group decreased gradually. The Gram-bacteria PLFA/Gram+ bacteria PLFA, Fungi PLFA/Bacteria PLFA, and Unsaturated PLFA/saturated PLFA ratios were decreased according to the increasing temperature gradually. Principal component analysis using PLFA profiles showed that microbial community structures were composed differently by temperature factor at both 75 days ($10^{\circ}C$) and 270 days ($30^{\circ}C$). In conclusion, Soil microbial community structure showed relative sensitivity and seasonal changes as affected by temperature and organic matter type.

• Korean Business Review
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• v.21 no.1
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• pp.91-117
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• 2008

Since the late 20th century, due to the globalization of markets and the rapid developments of information and communication technologies, the world has entered into the age of fierce competition. With their abundant low-cost labor, former communist countries such as China, Russia and East Europe and former low-developed countries such as India and Brazil have received foreign investments from major industrial companies. Thus, there are no other alternatives remained for Korea and OECD countries other than moving the industrial economies to the knowledge based innovation systems. In the knowledge based innovation systems, economic developments and employments of regions and nations depend solely on companies situated in their territories. In this article, after reviewing the current state of technological based innovation small firms in korea, we provide a theoretical framework to promote the level of technology based innovation and entrepreneurship. The theoretical framework for analysis and policy suggestions is based on the Schumpeter's value system model that consist of supply factors, demand factors, and supporting institutions. In order to create more innovative small businesses, we insist on the followings. First, more R&D and innovation activities related with promising new technologies should be performed. Second, more R&D funds for technological innovation small companies should be provided from governments. Third, more M&A transactions and technology transactions should be marketed freely and competitively. Fourth, more business incubating services and venture capital services should be provided. Fifth, entrepreneurship and innovation culture should be popular and institutionized among people.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.1
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• pp.64-69
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• 2004

The deficiency of the neurotransmitter acetylcholine(ACh) is responsible for the initiation of Alzheimer's disease. In addition, there is a simple evidence that oxidative stress significantly increases in persons with Parkinson's disease compared to age-matched healthy persons. Therefore, the objective of the study was to investigate the neurodegeneration inhibitory effect of soybean(Glycine Max) and Yak-Kong(Rhynchosia Nolubilis) by measuring the degree of inhibiting Acetylcholinesterase (AChE) catabolizing the ACh and the free radical scavenger effect in vitro. AChE was measured by the minor modified Ellman assay. Free radical scavenging activity was measured using l-diphenyl-2-picrylhydrazyl (DPPH). First, the MeOH extracts of Soybean and Yak-Kong showed the AChE inhibiting activity of 62.0$\pm$2.43％ and 65.0$\pm$3.29％ at the 5 mg/$m\ell$ concentration. The 50％ inhibitory concentration ($IC_{50}$/) of AChE was 1.96 and 1.31 mg/$m\ell$ in the MeOH extracts of soybean and Yak-Kong. Second, the MeOH extracts of soybean and Yak-Kong showed the free radical scavenger activity of 23.1$\pm$4.26％ and 80.7$\pm$4.61％ at the 5 mg/$m\ell$. IC50 of free radical scavenger activity in Soybean and Yak-Kong was 13.00 and 1.41 mg/$m\ell$ in MeOH extracts and was 5.95 and 2.74 mg/$m\ell$ in hot-water extracts, respectively. In this study, the extracts of Soybean and Yak-Kong showed powerful effects in the AChE inhibition and free radical scavenging. The extracts of Soybean and Yak-Kong were expected to prevent the many neurodegenerative diseases.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.2
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• pp.69-76
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• 2015

This paper aims to analyze how the Venture Business Tendency of North Korean refugees affects social adaptation and family health, and to provide proposals for policy making on the issue. For the purpose, we specifically suggest analysis of activation plan that 48 Venture Business North Korean managed Enterprise types, Entrepreneur type, Business type, Gender, Profit etc. As a result of analysis of actual proof, First, The Venture Business North Korean refugees managed need to consult to be technology business professionally because they features to be self-employment than expertise and knowledge basis type. Second, the rate of success of North Korean refugees is researched that female is higher than male. Third, to support Venture Business of North Korean refugees, they need one on one incubating support syspen why they are inexperienced in network, technical skills. Fourth, Venture Business Tendency of North Korean refugees affects social adaptation and family health. Since mid 1990's, North Korean refugees have come to South Korea through China or third countries due to collapsing economy of North Korea. In an effort to help those escaping from North Korea, the Seoul government provided them with a 3-month settlement program. But they have had experienced difficulties in communication, cultural assimilation, and confusion in their value system and identity. For the purpose, one-on-one interview was carried out on 45 North Korean refugees living in Seoul and neighboring cities, and the interviewed group was classified into three categories: single households, single-parent families and families with parents. The study findings demonstrated four policy alternatives to help improve quality of life of North Korean refugees and to help their successful settlemen.

• Journal of Food Hygiene and Safety
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• v.34 no.6
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• pp.571-575
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• 2019

Fungal occurrence during production of dried red pepper was investigated using red pepper samples collected at harvest, before and after washing, and before, during or after drying. Fungal incidence was evaluated by counting the number of fungal colonies grown after incubating random pepper cuts on potato dextrose agar plates. Washing with ground water had no significant effect on reduction of fungal contamination. Fungal increase was observed in some samples, and the insides of washer and containers were contaminated with fungi. Drying caused significant fungal increase regardless of drying method although the fungal incidence after machine drying was lower than that after greenhouse drying. Fungal increase was observed in the samples being dried in a greenhouse and some mycotoxigenic species were also detected. Therefore, the most important control point for fungal contamination during dried pepper production appears to be the drying process, especially in a greenhouse.

• Korean Journal of Animal Reproduction
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• v.16 no.1
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• pp.7-14
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• 1992

These experiments were designed to investigate the effects of glycosaminoglycans(GAGs), which maybe produced by cumulus cells, on in vitro maturation process of bovine follicular oocytes. The rates of in vitro maturation of bovine oocytes were examined after incubating with the various concentrations of a hyaluronic acid, chondroitin sulfate, or heparin for 26 hours. The results obatained in these experiments were summarized as follows : 1. When the cumulus or removed oocytes treated with hyaluronic acid(200, 400, 800 and 1, 600$\mu\textrm{g}$/ml), the maturation rates of cumulus-removed oocytes were 48.6, 59.4, 68.4 and 61.3% respectively. Especially, at a concentration of 800$\mu\textrm{g}$/ml, the maturation rates(68.8%) of cumulus-removed oocytes were slightly lower than that(78.3%) of cumulus-enclosed oocytes. However, the treatment of hyaluronic acid showed significantly higher maturation rates compared to that(48.4%) of control group of cumulus-removed oocytes(p<0.05). Therefore, these results suggest thate hyaluronic acid had a beneficial effect on maturation of bovine follicular oocytes. 2. The maturation rate of cumulus-free oocytes treated with chondroitin sulfate(200, 400, 800 and 1, 600$\mu\textrm{g}$/ml) was 52.3, 56.1, 55.9 and 52.2% respectively. These rates were not different from those(52.9%) of control group. However, these rates in cumulus-free oocytes were significantly lower than that(79.0%) in cumulus-enclosed oocytes(p<0.01). Therefore, these results suggest that chondroitin sulfate do not affect on the maturation of oocytes. 3. In cumulus-free oocytes cultured with different heparin concentration, the maturation rates were ranged from 48.5 to 52.1%, showing no differencies from that(50.7%) of control group. However, these rates were significantly lower than 80.0% in cumulus-enlosed oocytes(p<0.01). 4. The nuclear maturaton of oocytes was increased by treatment of each of three glycosaminoglycans(hyaluronic acid, chondroitin sulfate, and heparin). In addition, the treatment of mixed together showed the significant additive effect. Hyaluronic acid was more effective than chondroitin sulfate and heparin were.

• Applied Biological Chemistry
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• v.27 no.2
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• pp.100-106
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• 1984

Five subcellular fractions were obtained by successive centrifugation from the liver of rats within 6 hours of life and characterized by comparing marker compound or marker enzyms. After incubating $3{\beta}$-hydroxy-$5{\alpha}$-pregnan-20-one with the each fraction, the steroids were analyzed by TLC, GLC and GC-MS. A $6{\alpha}$-hydroxylase which hydroxylizes the tetra-hydrogenated compound of progesterone, $3{\beta}$-hydroxy-$5{\alpha}$-pregnan-20-one, was localized in the crude plasma membrane fraction, but not in the microsome fraction. The maximum 6α-hydroxylation was observed at pH 7.0. While this 6α-steroid hydroxylase was not able to hydroxlyze the progesterone, the $3{\alpha}$-isomer was hydroxylized at the $6{\alpha}$-position.

• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.1
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• pp.204-219
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• 1997

The use of fluoride is one of the most effective methods for caries prevention. Fluoridation of public water supply has been recognized, for many years, as an effective way to reduce dental caries. The fluoride supplement has been recommended when the natural fluoride was unavailable or below the optimal range. However the mechanism of caries prevention by fluoride has not yet been clarified and it is well known that an overdose of fluoride results inacute and chronic toxicity, especially dental fluorosis. Fluoride mouthrinsing solution is widely used in dentistry due to its effectiveness in carrying anticariogenic action. Understanding the effects of fluoride mouthrinsing solution on human gingival fibroblasts will provide the safety rationale for its use during the caries preventive therapy. The purpose of this study was to evaluate the cytotoxic effect of fluoride mouthrinsing solution on the human gingival fibroblast in vitro. The human gingival fibroblasts were cultured from healthy gingiva on the extracted deciduous teeth of children. Cells were inoculated into a 24-well plate with $1{\times}10^4cells/well$ of medium at $37^{\circ}C$, 100% humidity, 5% $CO_2$ incubator for 24 hours. And the cells were counted by using the hemocytometer at each designed study. Human gingival fibroblasts were cultured in growth medium after one minute application range of 0.02%-0.2% NaF solution and 0.1% $SnF_2$ solution. The cells used in this study were between fifth to eighth passage number. The cell morphology was examined by inverted microscope and cell proliferation was measured by incorporating $[^3H]$-thymidine into DNA. DNA synthesis by human gingival fibroblasts was assessed by $[^3H]$-thymidine uptake assays while the cell activity was measured by MTT assay. Each concentrated fluoride mouthrinsing solution was estimated for its biocompatability with fibroblasts by the tissue culture technique. The results of this study were as follows : 1. It was observed that at 0.05%, 0.2% NaF mouthrinsing solution the cytoplasmic processes became globular. When 0.1% $SnF_2$ mouthrinsing solution was applied, the cytoplasmic process and cell morphology were disappeared. 2. DNA synthetic activity was reduced regardless of the concentration of the fluoride mouthrinsing solution. However, the result is statistically insignificant except 0.1% $SnF_2$ mouthrinsing solution(p<0.05). 3. Our results indicate that 0.02%, 0.05% concentrations of NaF mouthrinsing solution caused minimal cytotoxicity. But 0.2% NaF and 0.1% $SnF_2$ concentration were a significant difference between the cell activity in the experimental group and control group (p<0.05). 4. After appling 0.05% & 0.02% NaF fluoride mouthrinsing solution, cell activity was restored to the control groups level according to incubating time. The results suggest that direct exposure to fluoride solution inhibits gingival fibroblast activity. Therefore, for the most effective use of fluoride use, lowering the concentration of fluoride mouthrinsing is advisable because it maintains biocompatability and free ion in the oral fluid.

• Journal of the korean academy of Pediatric Dentistry
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• v.47 no.2
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• pp.188-195
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• 2020

This study is aimed to evaluate and compare the surface roughness and microbial adhesion to alkasite restorative material (Cention N), resin-modified glass ionomer (RMGI), and composite resin. And to examine the correlation between bacterial adhesion and surface roughness by different finishing systems. Specimens were fabricated in disk shapes and divided into four groups by finishing methods (control, carbide bur, fine grit diamond bur, and white stone bur). Surface roughness was tested by atomic force microscope and surface observation was performed by scanning electron microscope. Colony forming units were measured after incubating Streptococcus mutans biofilm on specimens using CDC biofilm reactor. Cention N surface roughness was less than 0.2 ㎛ after finishing procedure. Control specimens of resin and Cention N specimens were significantly (p = 0.01) rougher. Pearson correlation coefficient (PCC = 0.13) indicated a weak correlation between surface roughness and S. mutans adhesion to the specimens. Compared with resin specimens, RMGI and Cention N showed lower microbial adhesion. Surface roughness and bacterial adhesion were not significantly different, regardless of the finishing systems.