• Clean Technology
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• v.16 no.4
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• pp.284-291
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• 2010

Nitrous oxide ($N_2O$) is a greenhouse material which is hard to remove. Even with a catalytic process it requires a reaction temperature, at least, higher than 670 K. This study has been performed to see the effects of Ce addition to the mixed oxide catalyst which shows the highest activity in decomposing $N_2O$ completely at temperature as low as 473 K when CO is used as a reducing agent. Mixed metal oxide(MMO) catalyst was made through co-precipitation process with small amount of Ce added to the base components of Co, Al and Rh or Pd. Consequently, the surface area of the catalyst decreased with the contents of Ce, and the catalytic activity of direct decomposition of $N_2O$ also decreased. However, in the presence of CO, the activity was found high enough to compensate the portion of activity decrease by Ce addition, so that it can be ascertained that the catalytic activity and stability can be maintained in the CO involved $N_2O$ reduction system when Ce is added for the physical stability of the catalyst.

• Journal of Adhesion and Interface
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• v.10 no.3
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• pp.117-126
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• 2009

Epoxy/anhydride systems with silica filler were studied to improve the cure behavior and characteristics. To study the curing process of epoxy/anhydride using DSC and a stress rheometer, it was observed that gelation temperature increased by increasing the thermal rate or in high isothermal conditions, while it was observed that the degree of cure at gelation decreased. Thermal stability of the epoxy/anhydride system showed any increment by increasing silica contents, except slight decrease of weight by containing humidity. The epoxy resin cured with 30% of silica filler decreased coefficient thermal expansion (CTE) about 33% to show $40ppm/^{\circ}C$. Specimens filled with 30 wt% of silica showed 60% increase in storage modulus at $30^{\circ}C$ to show 3909 MPa compared with neat resin to 2,377 MPa. Epoxy/anhydride systems with surface treated silica by silane coupling agent decreased storage modulus.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.1
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• pp.69-77
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• 2013

Jujube is a functional food, containing medicinal ingredients without side effects. Jujube can relieve digestive upset, inhibit tumor growth and protect the liver. It includes sterols, alkaloids, saponins, vitamins, organic acids, and amino acids. Jujube has also received attention as an anticancer agent and as a diet food. However, it is rare to find yogurt made with jujube, so we considered adding jujube powder to yogurt to popularize it as a new health food. We made yogurt with jujube powder at 0, 1, 2, 3, and 4%. We measured pH, acidity, color properties (brightness, redness, yellowness), viscosity, sensory qualities (color, flavor, taste, overall quality). We also experimented with storage stability at intervals of 1, 5, 10, 15, and 20 days. The results showed that pH increased significantly (p<0.001) with increasing amounts of added jujube powder. The pH also rose significantly with longer storage, but tended to decrease after 20 days. Acidity was reduced during the storage period. Viscosity was highest with 1% added jujube powder (p<0.001) on day 5 of storage (p<0.001). The L color value decreased as the amount of added jujube powder increased, whereas the a-value (redness) and b-value (yellowness) increased (p<0.001). In an sensory test, color in samples with 0, 1, and 2% jujube powder exhibited the highest values (p<0.01), but no significant differences in flavor or texture were observed. Sweetness and sourness were highest in the yogurt with 3% jujube powder (p<0.05). Overall quality tended to be higher for yogurt with 3% jujube powder, but the difference was in significant. Taken together, our results indicate that yogurt with 3% jujube powder may the most suitable for manufacturing purposes.

• Microbiology and Biotechnology Letters
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• v.18 no.5
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• pp.460-465
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• 1990

Regeneration of protoplast was effective by preincubating spore suspension containing 30$\mu g$/ml of 2-DG for 4 hours, and CBE medium containing casamino acid, bovine serum albumin, ergosterol and myoinositol was found to be more efficient than any other regeneration medium tested in this experiment. The regeneration frequency was about 30%. Optimal conditions for conidial protoplast fusion were obtained by treatment of protoplasts with 10 mM $CaCl_2$ and 30% polyethylene glycol 4000 (pH 7.5) as fusogenic agent at $37^{\circ}C$ for 10 minutes. The fusion frequency was $8.2\times 10^{-4}$. The higher productivity of enzyme of fusant FWN-56 was achived: 2.3-fold for CMCase, 1.5-fold for avicelase, 1.8-fold for $\beta$-glucosidase and 2.5-fold for xylanase compared to that obtained in two parental strains. The genetic stability of fusant after maintenance on minimal medium for more than 4 weeks was high because segregant rate was below 1%. The conidial DNA content of fusant was 1.4-1.6 times higher than that of the parental strains, The nucleus size of fusants were also higher than that of each parental strains.

• Polymer(Korea)
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• v.29 no.3
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• pp.253-259
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• 2005

Polyurethanes, synthesized by polyester polyols and aliphatic or aromatic diisocyanates for a crease resist finishing agent, were prepared by two-step reactions, that is, prepolymer synthesis and chain extension. The structures of synthesized polyurethanes were confirmed by the measurement of FT-IR and $^1H$-NMR spectrometer. The number average molecular weight ($\bar{M}_n$) and the weight average molecular weight ($\bar{M}_w$) of the polyurethane with aromatic diisocyanate (MDI) were higher than those of the synthesized polyurethanes with aliphatic diisocyanate (HDI, $H_{12}MDI$). The glass transition temperatures ($T_g$) of soft segments in polyurethanes with MDI, HDI, $H_{12}MDI$ were -25,-42 and -50$^{circ}C$, respectively. In the polyurethanes obtained by two-step reaction, thermal stability and tensile strength increased with increasing hard segment contents, whereas elongation at break decreased with increasing hard segment contents.

• Parasites, Hosts and Diseases
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• v.44 no.4 s.140
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• pp.331-341
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• 2006

Actin binding proteins play key roles in cell structure and movement particularly as regulators of the assembly, stability and localization of actin filaments in the cytoplasm. In the present study, a cDNA clone encoding an actin bundling protein named as AhABP was isolated from Acanthamoeba healyi, a causative agent of granulomatous amebic encephalitis. This clone exhibited high similarity with genes of Physarum polycephalum and Dictyostelium discoideum, which encode actin bundling proteins. Domain search analysis revealed the presence of essential conserved regions, i.e., an active actin binding site and 2 putative calcium binding EF-hands. Transfected amoeba cells demonstrated that AhABP is primarily localized in phagocytic cups, peripheral edges, pseudopods, and in cortical cytoplasm where actins are most abundant. Moreover, AhABP after the deletion of essential regions formed ellipsoidal inclusions within transfected cells. High-speed co-sedimentation assays revealed that AhABP directly interacted with actin in the presence of up to $10{\mu}M$ of calcium. Under the electron microscope, thick parallel bundles were formed by full length AhABP, in contrast to the thin actin bundles formed by constructs with deletion sites. In the light of these results, we conclude that AhABP is a novel actin bundling protein that is importantly associated with actin filaments in the cytoplasm.

• Journal of Pharmaceutical Investigation
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• v.33 no.4
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• pp.287-292
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• 2003

A novel antitumor agent, antibody-endostatin fusion protein $(anti-HER2/neu\;IgG3C_H3-Endostatin,\;AEFP)$ formed by genetic engineering procedure from antibody (Ab) which specifically targets to tumor cells ad angiogenesis inhibitor, endostatin (Endo) that has excellent antitumor effect, minimizes the toxicity of normal cells and selectively kills only tumor cells. The purpose of this study is to evaluate the phamacokinetic parameters and to analyze the localization of AEFP. After an intravenous injection of $150\;{\mu}l\;(5\;{\mu}Ci)\;[^{125}I]Ab,\;[^{125}I]AEFP$ to mice, blood was collected though retroorbital plexus from 15 min to 2880 min. Following the jugular vein injetion of $150\;{\mu}l\;(10\;{\mu}Ci)\;[^{125}I]Endo$, blood was collected by the use of carotid artery cannulation from 0.25 min to 30 min. Consequently, Endo was very rapidly removed from plasma compartment within 30 min. On the other hand, AEFP similar to Ab was slowly cleared from plasma. Also, Endo was metabolized about 40% within 30 min. However, AEFP was shown to metabolize less than 10% within 2880 min. The organ distribution of Endo was in order kidney, lung, spleen. Both Ab and AEFP were localized in order spleen, kidney, liver. Futhermore the tumor/blood distribution ratio of AEFP at 96 hours after injection is about 20 times higher than it of Endo at one hour after injection. In conclusion, these studies demonstrate that the anti-cancer or suppression of angiogenesis effect of Endo may be improved by the use of AEFP because the longer half life and stability of AEFP is able to selectively target antigens expressed on tumors.

• Economic and Environmental Geology
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• v.31 no.4
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• pp.291-296
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• 1998

Pedogenic hematite is a well known agent for sink of pollutants and nutrients and for aggregation of particles in soils. Changes in physical and chemical properties of two sandy loam soils (Anahuac and Crowley soils) from the Southern Coastal Plain, the United States of America, were tested after adding finely ground crystalline hematite prepared for drilling fluid weighting material. There was an increase in hydraulic conductivity (HC) of the soils with addition of up to 3% by weight of hematite but a decrease in HC with addition of more hematite. The aggregate stability (AS) of the soils was not affected by adding hematite. Anahuac soil with higher content of organic matter and lower sodium adsorption ratio (SAR) had higher values of HC and AS than Crowley soil. Adding hematite also resulted in a slight increase in zinc (Zn) adsorption by the soils, but had no influence on the adsorption of phosphate.

• Journal of Conservation Science
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• v.8 no.1 s.11
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• pp.28-32
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• 1999

The performance of dimensional stabilization of lactitol, PEG (Mw, 4000), and sucrose was evaluated for thin sections of oak wood (Quercus sp.) that had been buried in underground for presumably 1500 years. Thin wood sections of the specimen were soaked for three and seven days in each stabilizing agent with wide concentration ranges of 10, 30, 50, and $70\%$ by weight. Sucrose showed the largest weight gain among three agents, and the shrinkage of cross sections were found to be $1\%\;and\;4\%$ for three and seven days soaking, respectively. The result showed that sucrose among three stabilizing agents used was the best for the dimensional stabilization of the oak wood.

• Journal of Microbiology and Biotechnology
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• v.24 no.8
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• pp.1096-1104
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• 2014

$\small{L}$-Asparaginase from gram-positive bacteria has been poorly explored. We conducted recombinant overexpression and purification of $\small{L}$-asparaginase from Staphylococcus sp. OJ82 (SoAsn) isolated from Korean fermented seafood to evaluate its biotechnological potential as an antileukemic agent. SoAsn was expressed in Escherichia coli BL21 (DE3) with an estimated molecular mass of 37.5 kDa, determined using sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Consistent with asparaginases in gram-negative bacteria, size-exclusion chromatography determined SoAsn as a homodimer. Interestingly, the optimal temperature of SoAsn was $37^{\circ}C$ and over 90% of activity was retained between $37^{\circ}C$ and $50^{\circ}C$, and its thermal stability range was narrower than that of commercial E. coli $\small{L}$-asparaginase (EcAsn). Both SoAsn and EcAsn were active between pH 9 and 10, although their overall pH-dependent enzyme activities were slightly different. The $K_m$ value of SoAsn was 2.2 mM, which is higher than that of EcAsn. Among eight metals tested for enzyme activity, cobalt and magnesium greatly enhanced the SoAsn and EcAsn activity, respectively. Interestingly, SoAsn retained more than 60% of its activity under 2 M NaCl condition, but the activity of EcAsn was reduced to 48%. Overall, the biochemical characteristics of SoAsn were similar to those of EcAsn, but its kinetics, cofactor requirements, and NaCl tolerance differed from those of EcAsn.