• Journal of the Korean institute of surface engineering
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• v.37 no.2
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• pp.71-75
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• 2004

The technology of $C_{60}$ fullerite films preparation by means of gas-phase deposition and structure of fullerite films are described. A three-channel flow plant was used to obtain fullerite films. The films were deposited in the flow of inert gas under reduced pressure onto a cooled silicon or sapphire substrate placed inside the reaction chamber of the plant. The plant allows one to obtain the films of pure fullerenes and to synthesise the films from fullerene compounds and doped fullerenes. The structure of two types of films were investigated by FE-SEM and SEM techniques: pure fullerite films onto silicon and sapphire substrates as well as compound films were studied by FE-SEM technique. All samples have shown columnar structure with high level of porosity. The synthesis of films composed of fullerene and its compounds for use in electronics is demonstrated to be promising. For example, experiments confirm the possibility to use fullerite films in sensor electronics to produce humidity and thermal sensors. It is also possible to use the sensitivity of these films to isotropic pressure. The experiments with $C_{60}$-Cu-J films have shown quite strong dependence of their resistance on pressure of different sort of medium-gas that could be used in gas-sensitive sensors. The structure and preparation technology of resistive sensor based on fullerite films are described.bed.

• Particle and aerosol research
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• v.6 no.2
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• pp.51-59
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• 2010

ZnO quantum dots embedded in a silica matrix without agglomeration were synthesized from $TEOS:Zn(NO_3)_2$ solutions in one-step process by aerosol-gel method. It was successfully demonstrated that the size of ZnO Q-dots could be controlled from 2 to 7 mm verified by a high resolution transmission electron microscope observation. The line scanning energy dispersive X-ray spectroscopy(EDS) revealed that the Q-dots existed preferentially inside SiO2 sphere when Zn/Si < 0.5. However, the Q-dots distributed homogeneously all over the sphere when Zn/Si > 1.0. Blue-shifted UV/Vis absorption peak observation confirmed the quantum size effect on the optical properties. The photoluminescence(PL) emission peaks of the powders at room temperature were consistent with previous reports in the following aspects: 1) PL characteristics are dominated by two peaks of deep-level defect-related emissions at 2.4 - 2.8 eV, 2) the first defect-related peak at 2.4 eV was blue shifted due to the quantum size effect with decreasing the concentration of $Zn(NO_3)_2$(decreasing the size of ZnO q dots). More interestingly, the existence of surface-exposed ZnO q dots affects greatly the second defect PL peak at 2.8 eV.

• Journal of Microbiology and Biotechnology
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• v.11 no.1
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• pp.131-137
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• 2001

Previous work has identified that only the catabolite responsive element A (creA; previously called cre-2) out of two potential cre sequences (cre-1: nucleotide +160 to +173 and cre-2: +173 to +186), recognized within the coding region of the xylanaseA gene (xynA) of Bacillus stearothermophilus No.236, was actually, was actually involved in the carbon catabolite repression(CCR) of xynA expression in B. subtilis. However, the level of CCR of xynA expression in the original B.stearothermophilus No.236 strain (70-fold repression). Therefore, to search for an additional cre element in the promoter region, the upstream region of the xynA gene was subcloned by chromosome walking, and as a result, another potential cre element (nucleotide -124∼-137; designated creB) was recognized in this region. The cre-like sequence revealed a high homology to the cre consensus sequence. The xylanase activity of B. subtilis MW15 bearing pWPBR14 (containing creA and creB) cultured in a medium containing xylose as the sole carbon source was about 7.7 times higher than that observed for the same culture containing glucose. B. subtilis MW15 bearing pWPBR23 (containing only creA) produced an activity about 2.4 times higher. This pattern of CCR was confirmed using derivatives of xynA::aprA fusion plasmids. Furthermore, a measurement of the amounts of the xynA transcript showed a similar pattern as that for the production of xylanase. In addition, the synthesis of xylanase in B. subtilis QB7115 [a catabolite control protein A (ccpA) mutant strain] carrying pWPBR14 was almost completely relieved from glucose repression. Together, these results lead to a conclusion that the CCR of the expression of the xynA gene is mediated by CcpA binding at creA and creB sites in B. subtilis.

• Applied Biological Chemistry
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• v.36 no.3
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• pp.191-196
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• 1993

This method using the synthesis substrate of $5-bromo-4-chloro-3-indolyl-{\alpha}-galactoside\;(X-{\alpha}-Gal)$ was examined for the differential enumeration of Bifidobacteria and lactic acid-producing bacteria. Bifidobacteria possess a high level of ${\alpha}-galactosidase$ activity. Bifidobacterium longum KCTC 3215 exhibited the highest ${\alpha}-galactosidase$ specific activity (8.57 units/mg protein). Determination of ${\alpha}-galactosidase$ activity using the PNPG procedure showed that Lactobacillus, Streptococcus, Pediococcus, and Leuconostoc strain had lower ${\alpha}-galactosidase$ activity as compared to Bifidobacteria. The $X-{\alpha}-Gal$ based medium is useful to identify Bifidobacteria among lactic acid-producing bacteria since the enzyme action of ${\alpha}-galactosidase$ spills $X-{\alpha}-Gal$ substrate and releases indol which impacts a blue color to Bifidobacterial colonies on agar plates. All strains of Bifidobacteria appeared as blue colonies on MRS agar medium supplemented with $100\;{\mu}M\;X-{\alpha}-Gal$ while colonies of other lactic acid-producing bacteria appeared white or light blue.

• Journal of Nutrition and Health
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• v.36 no.8
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• pp.819-827
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• 2003

Linoleic acid [LA; 18: 2 (n-6)] is the most abundant polyunsaturated fatty acid in human skin. The exclusion of LA from diet induces epidermal hyperproliferation, which is reversible by the inclusion of LA in diet, and hence, LA is heralded as an essential fatty acid (EFA). Since safflower oil (SO) has been widely recognized as the major dietary source of LA and Arctii Fructus (Arctium lappa L.) is recently reported to contain high level of LA, we compared the antiproliferative effects of SO and Arctii Fructus in this study. Epidermal hyperproliferation was induced in guinea pigs by hydrogenated coconut oil (HCO) diet for 8 wk. During following 2 wk, EFA deficient guinea pigs were fed diets of safflower oil (group HS), water extract of Arctii Fructus (group AW) or organic extract of Arctii Fructus (group AO). Normal control group was fed SO containing diet (group SO) and EFA deficient group was fed HCO containing diet (group HCO) for 10 wk. Epidermal hyperproliferation was reversed in groups AO (55.9% of group HCO) and HS(74.1% of group HCO). However, the thymidine incorporation into epidermal DNA of group HS was greater than of normal control group SO. Epidermal hyperproliferation was not reversed in group AW. The accumulations of LA into phospholipids and ceramides, and of 13-hydroxyoctadecadienoic acid (13-HODE), the potent antiproliferative metabolite of LA in the epidermis of group AO were greater than of group HS. In contrast, the de novo synthesis of ceramides, the major lipids maintaining epidermal barrier, did not differ between all of groups. Together, our data demonstrate that organic extract of Arctii Fructus is more prominent than safflower oil in reversing epidermal hyperproliferation by inducing the higher accumulations of LA and 13-HODE in the epidermis of guinea pigs.

• IMMUNE NETWORK
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• v.10 no.1
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• pp.15-25
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• 2010

Background: Rat mast cells were regarded as a good model for mast cell function in immune response. Methods: Rat bone marrow mast cells (BMMC) were prepared both by recombinant rat IL-3 (rrIL-3) and by recombinant mouse stem cell factor (rmSCF), and investigated for both proliferation and differentiation in time course. Rat BMMC was induced by culture of rat bone marrow cells (BMCs) in the presence of both rrIL-3 (5 ng/ml) and rmSCF (5 ng/ml). Culture media were changed 2 times per week with the cell number condition of $5{\times}10^4/ml$ in 6 well plate. Proliferation was analyzed by cell number and cell counting kit-8 (CCK-8) and differentiation was by rat mast cell protease (RMCP) II and histamine. Results: Cell proliferation rates reached a maximum at 8 or 11 days of culture and decreased thereafter. However, both RMCP II production and histamine synthesis peaked after 11 days of culture. By real time RT-PCR, the level of histidine decarboxylase mRNA was more than 500 times higher on culture day 11 than on culture day 5. By transmission electron microscopy, the cells were heterogeneous in size and contained cytoplasmic granules. Using gated flow cytometry, we showed that cultured BMCs expressed high levels of $Fc{\varepsilon}RI$ and the mast cell antigen, ganglioside, on culture day 11. Conclusion: These results indicate that rat BMMCs were generated by culturing BMCs in the presence of rrII-3 and rmSCF and that the BMMCs have the characteristics of mucosal mast cells.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.1
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• pp.124-130
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• 2013

In this paper, a new motion estimation algorithm with low-computational complexity is proposed to improve the performance of H.264/AVC. The proposed architecture uses the directions of the median motion vector which is computed by the motion vectors of the three neighbor macroblocks in Integer Motion Estimation. By using the directions of the vector, the proposed architecture has a single computational level instead of multi-computational levels in Integer Motion Estimation. The proposed motion estimation is synthesized using the TSMC 0.18um standard cell library. The synthesis result shows that the gate count is about 217.92K at 166MHz and it was improved about 69% compared with previous one.

• The KIPS Transactions:PartA
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• v.9A no.3
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• pp.379-386
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• 2002

This paper presents a scheduling approach for synthesizing pipelined datapaths under resource constraints. Our approach builds up a schedule based on gradual mobility reduction in contrast to other algorithms of previous researches, where an operation being scheduled is selected by using a priority function. The proposed method consists of a scheduling algorithm and a decision algorithm for detecting any violation against resource constraints. Our approach evaluates whether or not a scheduling solution can exist in case an operation temporarily is assigned to the earliest or latest control step among the assignable steps for the operation. If a solution cannot be found, it is impossible to assign the operation to that step due to a violation against resource constraints, and so we can eliminate that control step. This process is iterated until a reduction of mobility for all operations can not be obtained. Experiments on benchmarks show that this approach gains a considerable improvement over those by previous approaches.

• KSBB Journal
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• v.24 no.1
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• pp.96-100
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• 2009

One of the major drawbacks associated with the high-level expression of the recombinant proteins in Escherichia coli is the formation of insoluble inclusion bodies in the cytoplasm. Production of recombinant protein at reduced temperature has proven effective in improving the solubility of a number of structurally and functionally unrelated proteins, but a major limitation of using low temperatures for recombinant protein production in E. coli is the reduced rate of synthesis of the heterologous protein caused by the significant reduction of cell growth rate. Here we investigated the effect of co-expression of CspA, a cold-shock protein known to be RNA chaperone at low temperature, on the productivity of recombinant protein at various temperatures by using green fluorescence protein (GFP) as a model recombinant protein. We could observe that the co-expression of CspA enhanced the productivity of GFP at $15^{\circ}C$ by accelerating the growth of E. coli at the temperature. On the other hand, the CspA coexpression didn't affect the cell growth rate as well as the specific GFP production rate at other tested temperatures, $20^{\circ}C$, $25^{\circ}C$, and $37^{\circ}C$.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.43 no.1 s.307
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• pp.39-44
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• 2006

In this paper, search result list synthesis method is proposed using borda count method for still image retrieval based on MPEG-7 descriptors. MPEG-7 standardizes descriptors that extract feature information from media data. In many cases, using a single descriptor lacks of correctness, it is suggested to use multiple descriptors to enhance retrieval efficiency. In this paper, retrieval efficiency enhancement is achieved by combining multiple search results which are from each descriptor. In combining search result, newly calculated borda count method is proposed. Comparing current frequency compensated calculation, rank considered frequency compensation is used to score animage in database. This combining method is considered in Content based image retrieval system with relevance feedback algorithm which uses high level information from system user. In each relevance iteration step, adoptive borda count method is used to calculate score of images.