• The Korean Journal of Zoology
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• v.31 no.3
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• pp.185-190
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• 1988

To investigate whether malignant behavior of skin tumor correlates with changes in the level of proteolytic activities in skin tumors, rats were treated with 7,12-dimethylbenzanthracene followed by photbor ester. Tumors induced upon the treatrnents exhibited more than 20-fold increase in the activity of plasminogen activator and about 3-fold of plasmin-like activity. as compared to those in treated controls. Furthermore, the former activity was raised to about 6-fold even in the preneoplastic dssues of the skin tissues. On the other hand, the proteolytic activity against casein and insulin decreased to several-fold in the tumor tissues while antitrvpsin activity remained similar in both tumor and controls. Thus, the increase in the activities of plasmInogen activator and plasminlike enzyme appears to occur as a charaderistic to skin cancer and may involve in invasion and metsstasis of the tumor.

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.2
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• pp.162-165
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• 2003

In order to study the secretion of the human urokinase-type plasminogen activator, u-PA, from the yeast yarrowia lipolytica, three kinds of integrative expression vector were constructed. These vectors differed only in their secretion control legions, pre-, pre-dip-(dipeptide Stretch) or pre-dip-pro sequences of the alkaline extracellular protease, which were joined inflame to the human u-PA cDNA. The recombinant Y. lipolytica Strains, transformed with the expression vectors, secreted the hyperglycosylated u-PA. A fibrin plate assay of the culture supernatants showed that the hyperglycosylated u-PA proteins could catalyze fibrinolysis, and that the pre-dip sequence was the most efficient secretory signal for the secretion of the u-PA from Y. lipolyica. This result suggests that Y. lipolytica can be developed as a potential host for the production of recombinant human u-PA.

• Biotechnology and Bioprocess Engineering:BBE
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• v.1 no.1
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• pp.32-35
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• 1996

Amoving aeration-membrane (MAM) bioreactor was employed for the production of 2$\mu$g/mL of tissue type Plasminogen Activator (tPA)in serum free medium from normal human fibroblast cells. This system could maintain high cell density for long periods of steady state conditions in perfusion cultivation. Under normal operating condition, shear stress was as low as 0.65 dynes/$\textrm{cm}^2$ at the agitation speed of 80 rpm. Even though cell density gradually decreased with increasing agitation speed, tPA production increased linearly with increasing shear stress within a moderate range. This culture system allowed production of 2$\mu$g tPA/mL while maintaining a high cell denisty of 1.0$\times$107 viable cell/mL.

• Molecules and Cells
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• v.26 no.5
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• pp.486-489
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• 2008

Curcumin (diferuloylmethane), a pigment derived from turmeric, has anti-oxidant and anti-inflammatory activities. Accumulating evidence points to a biochemical link between increased oxidative stress and reduced bone density. Osteoclast formation was evaluated in co-cultures of bone marrow stromal cells (BMSC) and whole bone marrow cells (BMC). Expression of receptor activator of nuclear factor-${\kappa}B$ ligand (RANKL) was analyzed at the mRNA and protein levels. Exposure to curcumin led to dose-dependent suppression of osteoclastogenesis in the co-culture system, and to reduced expression of RANKL in $IL-1{\alpha}$-stimulated BMSCs. Addition of RANKL abolished the inhibition of osteoclastogenesis by curcumin, whereas the addition of prostaglandin $E_2$ ($PGE_2$) did not. The decreased osteoclastogenesis induced by curcumin may reduce bone loss and be of potential benefit in preventing and/or attenuating osteoporosis.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.277-280
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• 2003

The purpose of this study is for the active use of the fly ash, which is a by-product of the combustion pulverizes coal thermal power plants, to compensate for the lack of landfill and for conservation of energy, by using fly ash as the supplementary cementitious material, and to prove its possibility as the related products of the cement. First of all, we examined strength development of Micro grinding fly ash by elevating its fineness and using $Na_{2}SO_{4}$ as an activator to elevate pozzolanic reaction of fly ash. Following fly ash replacement ratio and curing temperature we hope to prove its properties to suggest its possibility in the concrete and cement industry. In case of water curing, the more fineness and higher annexing of activator is, the higher strength is, and the higher curing temperature is the more pozzolanic reaction happens.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.11a
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• pp.217-218
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• 2011

The advantages of blast-furnace slag concrete may include lower hydration heating velocity, restraint on concrete temperature increase, long-age strength improvement due to latent hydraulic reaction, improved water tightness, and repulsion to chemical erosion. These advantages contribute to the high quality of the blast-furnace slag concrete. However, the blast-furnace slag concrete has its limitations as well. These disadvantages may include retarded setting and elongated retention of mold due to the weak strength of early-age. Nevertheless, much research is currently under way to improve the aforementioned issues. To improve activity of blast furnace slag powder, alkaline irritants has been used. In this study, we analyze effect on activity fineness and rate of substitution of Alkali Activator toward activity.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.173-174
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• 2017

Recently, many experiments using industrial by-products have been going on in Korea and abroad. Most of the studies on blast furnace slag and fly ash have been conducted, and the blast furnace slag based two and three component experiments have been conducted in many places. Therefore, this study is an additional study of research using polysilicon sludge and paper ash, which is a study using existing industrial by-products based on blast furnace slag, as strength properties of alkali activator according to kind and mixing ratio and to obtain basic data do.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.256-257
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• 2017

This paper presented polymerization reactivity of fly ash based geopolymer with alkaline activator type. As a result, the compressive strength development properties of the geopolymer can be confirmed from the combination of the amorphous Si and Al contents in the fly ash and the alkaline activators. Although the direct correlation between the polymerization reactivity of the geopolymer and the development of compressive strength could not be confirmed through an X-ray diffraction analysis, it could be confirmed through scanning electron microscopy.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.789-792
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• 2006

The purpose of this study is to investigation the fundamental properties of alkali activated slag of type and concentration of alkali activator. In this paper sodium silicate, sodium carbonate and sodium hydroxide were used as alkaline activator and their concentration were 1, 3, 5 and 7 $Na_2O$ weight percent. The physical properties of alkali activated blast furnace slag cement mortar (AAS) were investigated by flow test and compressive strength. And the hydration properties of AAS characterized by X-ray diffraction and scanning electron microscope. Result show that Alkali activated slag mortar strengths were continuously increased with adding amount and ages. C-S-H were formed to be the main products up to 28days of hydration.

• Journal of the Korean institute of surface engineering
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• v.28 no.3
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• pp.152-163
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• 1995

A theoretical model which combines gaseous transport and solid state diffusion with the multi-component equilibrium at the gas/pack and gas/coating interfaces was used to study the kinetics of diffusion aluminide coating. The diffusion aluminide coatings were applied by pack cementation with Ni substrate under argon atmosphere in the high activity and the low activity pack containing $NH_4CL$ or $AlF_3$ activator. On the basis of the process conditions, the suggested model allows the surface composition, the growth rate of coating layers and the aluminium concentration profiles in coatings to be calculated. In the case of $NH_4$Cl activator, careful consideration was required in the analysis, because activator contains nitrogen and hydrogen as well as halogen element to activate the pack. A good agreement is obtained between the theoretical predictions and the experimental results.