• Journal of the Korean Chemical Society
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• v.31 no.6
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• pp.491-497
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• 1987

$ThO_2-Tm_2O_3$ (TDT) solid solutions containing 1,3,5,8,10, and 15 mol% $Tm_2O_3$ were synthesized from spectroscopically pure $ThO_2$ and $Tm_2O_3$ polycrystalline powders. The TDT solid solutions were indentified to the fluorite structure by the X-ray powder technique. The values of the lattice parameter were decreased with increasing amount of $Tm_2O_3$ incorporated. But, there was no linearity for the samples containing 8, 10, and 15 mol% $Tm_2O_3$. It was concluded that these samples became incomplete solid solutions. From the intensity analyses of X-ray diffraction patterns, the residual factor was found below 0.13 even for the 15 mol% TDT system. lt was confirmed from the DTA and TGA analyses that any phase transitions did not occur under the experimental condition executed. Comparing the pycnometric density with the lattice parameter obtained from XRD, it was suggested that the predominant defect model be an oxygen vacancy.

• Hwankyungkyoyuk
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• v.5 no.1
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• pp.112-137
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• 1993

As the concern with the creation of environmental problems and regulations about them becomes internationally growing, environmental cooperations with countries concerned are emerging as the first item on the political agenda. In case of South Korea, cooperations with countries in the Asian region is needed urgently. In particular, cooperations with North Korea will be an important factor to reunify the Korean peninsula as well as to solve environmental problems in South Korea. Accordingly, it is necessary to seek feasible alternatives and possibilities of coping with international environment in South and North Korea. This study is limited to literature study based on collecting materials and the testimony of former residents in North Korea. The period of study ranges from May to December in 1992. The research findings show the following environmental problems and alternatives : It is recognized in South Korea that the creation of environmental problems is product of economic development. Currently, the Korean government makes an effort to revise environmental administration and law, to encourage environmental education, and to proceed with environmental technology policies by establishing environmental policies together with economic development plans. North Korea ascribes the cause of environmental problems to colonial exploitation by Japan and the U.S. Environmental pollutants in North Korea is relatively less than South Korea, provisions such as environmental conservation movement, environmental education, and environmental administration and law are not well organized in the country. However, North korea will speed up its economic development to solve economic crises. Therefore, it is expected that industrial wastes, corrosion of nature, and water pollution will result in serious environmental problems. The fields expected to cooperate with South and North Korea are in the following : South Korea may adopt the model of the former East and West Germany and proceed to cooperate with North Korea in public sector as well as private sector. The possible programs are such as academic exchange to conserve environment, joint research in the area of the Demilitarized Zone, conservation of ecosystems around Imjin and Pukhan Rivers, South Korea's support of advanced environmental technology and industrial and financial aid to North Korea. Conflicts between countries concerned in the North East Asian region will be caused by the responsibilities of pollutions because of the seashore development of the Yellow Sea by South Korea and increasing seashore industrial complexes around the Yellow Sea in China, Therefore, it is desirable that the two countries will participate in organizations related to environment. Joint projects between South and North Korea will be as follows : 1. Construction of long-range monitoring system : 2. Investigation of the state of pollutions around the Yellow Sea and alternatives : 3. Construction of joint monitoring system to regulate the movement of pollutants : 4. Cooperation of environmental technology and exchange of information ; and 5. Support of Cooperation of environment in private sector. Efforts to cooperate with North korea is expected to overcome differences between the two countries as well as to encourage unification of the korean peninsula, which will lead to reducing the cost of environmental recovery. These efforts will also contribute to the maintenance for peace and stability on the korean peninsula as well as in the North East Asian region.

• Journal of Gifted/Talented Education
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• v.22 no.2
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• pp.427-450
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• 2012

This study was intended to develop a self-report wisdom scale for the elementary gifted students. For this, related literature was reviewed in depth and open ended questionnaire about the wisdom qualities was conducted. Based on these, a self-report wisdom scale, which was comprised of 42 items in 4 factors such as the situation judgment and problem-solving ability, the communication ability and skills, the emotional stability, the insight and adaptation, was developed. For this preliminary scale, 215 elementary gifted students were surveyed. And for the confirmatory factor analysis, 256 elementary gifted students participated. The results of the study were as follows. The fit of measurement model was found to be ${\chi}^2$=1596.46 (df=813, p=.00), TLI .90, CFI .91, RMSEA .046, indicating most of fit indexes were acceptable. The reliability for each of 42-item by the sub-factors also appeared to be good, showing that internal consistency reliability by the configuration factors was 0.86, .87, .89, .87 each relatively. In addition, to verify the validity of the wisdom scale, the convergent and discriminate validities were obtained through the correlation analysis among the psychological characteristics which were considered to be related to the wisdom. Finally, practical implications of the study were discussed in depth.

• Journal of Korea Society of Industrial Information Systems
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• v.22 no.4
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• pp.79-95
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• 2017

This Study Investigates Whether R&D Capabilities and Market Orientation have Significant Effects on Product Innovation Performance in Order to Enhance Customer Value and Technology Innovation Competitiveness Considering the Characteristics of Rapidly Changing Semiconductor Industry. In other Words, as in the Research Model, the Purpose of this Study is to Investigate the Causal Relationship between the Independent Variable, R&D Capability and Market Orientation, on Product Innovation Performance, which is a Dependent Variable, through the Moderating Variable of Technological Innovation Orientation. For this Study, we Conducted a Questionnaire Survey on the Employees of Development Companies in the Semiconductor Industry and Finally Collected 118 Valid Questionnaires. The Collected Data was Analyzed by Multiple Regression Analysis with Demographic Characteristics as Control Variable and Hierarchical Regression Analysis was Conducted with the Moderating Effects of Technological Innovation Orientation. The Results Showed that the Higher the R&D Intensity and the External Network Capacity, the Higher the Product Innovation Performance. Also, the Product Innovation Performance was Higher than the Customer Orientation and Competitor Orientation Among the Market Orientation. In Addition, only R&D Capability Confirms that Technology Innovation Orientation is Moderated. The Result of this Study is to Improve Understanding of R&D Capability and Market Orientation in Creating of Product Innovation Performance of Semiconductor Companies and to offer Valuable Research Data in Empirically Supporting that Technological Innovation Orientation is an Important Moderating Factor in Creating Firm's Product Innovation Performance and Sustainable Competitive Advantage.

• Journal of Life Science
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• v.16 no.4
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• pp.566-570
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• 2006

Pronuclear microinjection (PMI) is a primary method for producing transgenic mice and offers a powerful tool for investigating gene function in vivo. The method has several reported advantages and disadvantages. Here, we report another potential shortcoming. The survival rate of fertilized one cell-stage embryos was significantly reduced after PMI procedure (65.4% (1202/1838)). In addition, the proportion of embryos developing to full-term was also significantly lower than that of embryos not undergoing PMI (26.5% (319/1202) vs 41.9% (57/136)). Moreover, 3 out of 21 (14.3%) founder control mice which were non-transgene-carrying littermates of transgenic founders showed histopathological changes in their liver, which was comparable to that in of transgenic lineages (4 out of 27 (14.8%)). In conclusion, the mechanical damages in chromosomes occurring during PMI procedure may be a potential factor influencing phenotypes of transgenic mice.

• Journal of Life Science
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• v.22 no.10
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• pp.1371-1377
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• 2012

Fibrosis in kidney by internal and external factors causes progressive loss of renal function. Renal fibrosis is the inevitable consequence of an excessive accumulation of the extracellular matrix. TGF-${\beta}$ plays an important role in the process of renal fibrosis and stimulates the synthesis of profibrotic factors, including collagens, fibronectin, and plasminogen activator inhibitor (PAI-1). We examined the effect of Moringa oleifera Lam (moringa) extracts in a rat kidney fibrosis model. We found that moringa root extract suppresses protein expression/mRNA levels of Type I collagen, fibronectin, and PAI-1 induced by TGF-${\beta}$ in renal fibroblasts. Moringa root extract selectively inhibited phosphorylation of TGF-${\beta}$-induced $T{\beta}RII$ and the downstream signaling pathway (e.g., Smad4), and phospho-ERK, but not JNK, p38, or PI3K/AKT. These results suggest that moringa root extract can act against TGF-${\beta}$-induced renal fibrosis in rat kidney fibroblast cells by a mechanism related to its antifibrotic activity, which regulates expression of fibronectin, Type I collagen, and PAI-1 through $T{\beta}RII$-Smad2/3-Smad4 and ERK. Therefore, moringa root extract is an effective substance for fibrosis therapy and provides a new therapeutic strategy for diseases associated with elevated profibrotic factor synthesis.

• Journal of Life Science
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• v.24 no.9
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• pp.981-987
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• 2014

Foeniculum vulgare has long been prescribed in traditional medicine for the treatment of inflammation diseases. In this study, we aimed to investigate the inhibitory effects of the fruits of F. vulgare on lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells under non-cytotoxic ($100{\mu}g/ml$) conditions. The 80% methanol extract was subsequently partitioned successively with hexane, methylene chloride, ethyl acetate, and n-butanol, and the fractions so obtained were also examined for their anti-inflammatory effects. Among them, the hexane, methylene chloride, and ethyl acetate fractions inhibited nitric oxide (NO) and prostaglandin E2 (PGE2) production in LPS stimulated macrophages. The methylene chloride and ethyl acetate fractions also suppressed the productions of interleukin $(IL)-1{\beta}$ and IL-6 by down-regulating their mRNA levels in LPS stimulated RAW 264.7 cells. Furthermore, the ethyl acetate fraction strongly suppressed tumor necrosis factor (TNF)-${\alpha}$ at the protein and mRNA levels in LPS stimulated RAW 264.7 cells. These observations suggest that the anti-inflammatory actions of F. vulgare are due to inhibitions of the productions of NO, PGE2, and pro-inflammatory cytokines.

• Journal of Life Science
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• v.27 no.12
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• pp.1479-1485
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• 2017

Muscle atrophy due to aging, starvation, and various chronic diseases leads to a decrease in muscle fiber area and density due to reduced muscle protein synthesis and increased protein breakdown. This study investigated the effect of dexamethasone and hydrogen peroxide on the induction of muscle atrophy and expression of atrophy-related genes in differentiated C2C12 myotubes. C2C12 myoblasts were differentiated into myotubes in differentiation medium. During myoblast differentiation, muscle-specific transcription factors, such as myogenin, and MyoD expression increased. Differentiated C2C12 myotubes exposed to noncytotoxic levels of dexamethasone and hydrogen peroxide showed a decrease in myotube diameter, which was associated with up-regulation of muscle-specific ubiquitin ligases, such as muscle atrophy F-box (MAFbx)/atrogin-1 and muscle RING finger-1 (MuRF1), and down-regulation of myogenin and MyoD. These results demonstrated that dexamethasone and hydrogen peroxide induced atrophy through regulation of muscle-specific ubiquitin ligases and muscle-specific transcription factors in C2C12 myotubes. In this study, we confirmed the process of differentiation of C2C12 myoblasts into myotubes in in vitro experiments in the presence of atrophy. This muscle atrophy model of C2C12 cells induced by dexamethasone or hydrogen peroxide seems suited to studies of the mechanism of muscle atrophy suppression and to exploit the experiment for excavating new muscle atrophy.

• Journal of Microbiology
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• v.45 no.4
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• pp.305-310
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• 2007

The principal objective of this study was to compare the effects of whole and hydrolyzed cells (bifidobacteria) treated with gastrointestinal digestive enzymes on the activation of cloned macrophages. Seven different strains of Bifidobacterium obtained from swine, chickens, and rats, were digested with pepsin followed by pancreatin and the precipitate (insoluble fraction) and supernatant (soluble fraction) obtained via centrifugation. The RAW 264.7 murine macrophages were incubated with either whole cells, the precipitate, or supernatant at various concentrations. Pronounced increases in the levels of nitric oxide (NO), interleukin $(IL)-1{\beta}$, IL-6, IL-12, and tumor necrosis factor $(TNF)-{\alpha}$ were observed in the whole cells and precipitates, but these effects were less profound in the supernatants. The precipitates also evidenced a slight, but significant, inductive activity for NO and all tested cytokines, with the exception of $(TNF)-{\alpha}$ in the macrophage model as compared with the whole cells. By way of contrast, $(TNF)-{\alpha}$ production when cultured with whole cells (100 ng/ml) resulted in marked increases as compared with what was observed with the precipitates. The results of this study indicated, for the first time, that digested Bifidobacterium sp. can induce the production of NO and several cytokines in RAW 264.7 murine macrophage cells. In the current study, it was demonstrated that Bifidobacterium strains treated with digestive enzymes, as compared with whole cells, are capable of stimulating the induction of macrophage mediators, which reflects that they may be able to modulate the gastrointestinal immune functions of the host.

• Journal of the Korean Geotechnical Society
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• v.20 no.1
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• pp.109-120
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• 2004

There has been outstanding research on the soil-water characteristic curves of unsaturated soils over the past several decades. Unfortunately, unsaturated soil mechanics has not been considered as an important factor in Korea. In this paper, laboratory test and numerical analysis(SoilVision Professional ver 3.04) were performed to investigate the prediction method of soil-water characteristic curve and unsaturated permeability coefficient in reclaimed ground. The pressure cell, desiccator, and tensiometor tests were conducted on three types of reclaimed soils(dredged soil, sand, weathered granite soil). Numerical analysis was executed to compare the results with the laboratory test results and also compared with the results of each prediction method. Based on the laboratory test, three different types of soils have shown different soil-water characteristic curves. The hysteresis fir these soils is clearly defined. As a result of numerical analysis, Fredlund & Xing's method and Fredlund & Wilson's model proved to worke out well for reclaimed ground soils in Korea. Also, predicting method based on the soil-water characteristic curves from the particle-size distributions is flirty reliable for estimating unsaturated permeability coefficient.