• Journal of Industrial and Engineering Chemistry
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• v.68
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• pp.140-145
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• 2018

Bulky carbon layer uniformly distributed with nanoscale $Fe_2O_3$ was prepared via a direct carbonation of $Fe^{3+}$-polyacrylonitrile complexes at $700^{\circ}C$ under $N_2$ flow. The iron oxide carbon composites exhibited an excellent cycling performance for lithium storage with a reversible capacity of ${\sim}810mAh\;g^{-1}$ after 250 cycles at a current rate of $100mA\;g^{-1}$. The enhancement was mainly attributed to dual functions of bulky carbon layer which facilitated the lithium-ion diffusion and accommodated the volume changes of active $Fe_2O_3$ during charge/discharge process. Our novel chemical strategy is quite effective for scalable fabrication of high capacity lithium-storage materials.

• Journal of Industrial and Engineering Chemistry
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• v.68
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• pp.372-379
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• 2018

The improvement of $NO_x$ reduction by $Ag/{\gamma}-Al_2O_3$ with a hydrocarbon ($n-C_7H_6$) in the early state was investigated in a packed-bed dielectric barrier discharge plasma reactor. The results revealed that the combination of plasma with the catalyst enhanced $NO_x$ reduction efficiency at low operating temperatures, depending on the temperature and specific input energy. To sum up, the poor performance of the catalytic $NO_x$ reduction at low temperatures in the early stage before reaching thermochemical steady state can be greatly compensated for by using the atmospheric-pressure plasma generated in the catalyst bed.

• Advances in materials Research
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• v.7 no.3
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• pp.185-194
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• 2018

The mechanism of biological materials structure is very complex and has optimal properties compared to engineering materials. Top Neck mollusks shells, as an example of biological materials, have hierarchical structure, which 95 percent of its structure is Aragonite and 5 percent organic materials. This article detected mechanical properties of the Top Neck mollusks shell as a Nano composite using Nano-indentation method in different situations. Research findings indicate that mechanical properties of the Top Neck mollusks shell including elastic modulus and hardness are higher than a fresh one preserved in -50 centigrade and also a Top Neck mollusks shell preserved in environmental conditions. Nano-indentation test results are so close in range, overall, that hardness degree is 3900 to 5200 MPa and elastic modulus is 70 to 85 GPa.

• Journal of Industrial and Engineering Chemistry
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• v.67
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• pp.312-315
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• 2018

Although the reversibility of 10,12-pentacosadiynoic amino meta-acid(PCDA-mBzA) against temperature and pH was reported, the modulation of reversibility by ion adsorption at terminal functional group has not been investigated. In this work, we developed a simple method for modulating the reversibility of PCDA-mBzA films upon a thermal stimulus by cadmium ion adsorption inducing the breakage of the outer hydrogen bonding of two hydrogen bonds, which are responsible for the reversible properties of PCDA-mBzA. External reflection-Fourier transform infrared (ER-FTIR) analyses revealed that the hydrogen bonding between the carboxylic acid groups was broken through ion adsorption and only a single hydrogen bond between the amide groups remained in the PCDA-mBzA polymer. In addition, PCDA-mBzA films could recover their original property through cadmium ion desorption. These results present that the transition between reversibility and irreversibility can be modulated artificially simply through the adsorption and desorption of metal ions.

• Genomics & Informatics
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• v.2 no.3
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• pp.121-125
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• 2004

The purpose of this study was to investigate the use of decision tree for the classification of antimicrobial peptides. The classification was based on the activities of known antimicrobial peptides against common microbes including Escherichia coli and Staphylococcus aureus. A feature selection was employed to select an effective subset of features from available attribute sets. Sequential applications of decision tree with 17 nodes with 9 leaves and 13 nodes with 7 leaves provided the classification rates of $76.74\%$ and $74.66\%$ against E. coli and S. aureus, respectively. Angle subtended by positively charged face and the positive charge commonly gave higher accuracies in both E. coli and S. aureusdatasets. In this study, we describe a successful application of decision tree that provides the understanding of the effects of physicochemical characteristics of peptides on bacterial membrane.

• Molecules and Cells
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• v.27 no.1
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• pp.47-54
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• 2009

A cDNA clone for a transcript preferentially expressed during an early phase of flooding was isolated from Nicotiana tabacum. Nucleotide sequencing of the cDNA clone identified an open reading frame that has high homology to the previously reported glycine-rich RNA-binding proteins. The open reading frame consists of 157 amino acids with an N-terminal RNA-recognition motif and a C-terminal glycine-rich domain, and thus the cDNA clone was designated as Nicotiana tabaccum glycine-rich RNA-binding protein-1 (NtGRP1). Expression of NtGRP1 was upregulated under flooding stress and also increased, but at much lower levels, under conditions of cold, drought, heat, high salt content, and abscisic acid treatment. RNA homopolymer-binding assay showed that NtGRP1 binds to all the RNA homopolymers tested with a higher affinity to poly r(G) and poly r(A) than to poly r(U) and poly r(C). Nucleic acid-binding assays showed that NtGRP1 binds to ssDNA, dsDNA, and mRNA. NtGRP1 suppressed expression of the fire luciferase gene in vitro, and the suppression of luciferase gene expression could be rescued by addition of oligonucleotides. Collectively, the data suggest NtGRP1 as a negative modulator of gene expression by binding to DNA or RNA in bulk that could be advantageous for plants in a stress condition like flooding.

• Journal of Plant Biotechnology
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• v.37 no.3
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• pp.262-268
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• 2010

Antibodies are powerful and versatile tools to play a critical role in the diagnosis and treatment of many diseases. Their application has been enhanced significantly with the advanced recombinant DNA and heterologonous expression technologies, allowing to produce immunotherapeutic proteins with improved biofunctional properties. However, with currently available technologies, mammalian cell-based therapeutic antibody production, as an alternative for production in humans and animals, is often not plentiful for passive immunotherapeutics in treatment of many diseases. Recently, plant expression systems for therapeutic antibodies have become well-established. Thus, plants have been considered to provide an attractive alternative production system for therapeutic antibodies, as plants have several advantages such as the lack of human pathogens, and low cost of upstream production and flexible scale-up of highly valuable recombinant glycoproteins. Recent advances in modification of posttranslational processing for human-like glycosylation in transgenic plants will make it possible that plant can become a suitable protein expression system over the animal cellbased current production system. This review will discuss recent advances in plant expression technology and issues for their application to therapeutic antibody production.

• Journal of Microbiology and Biotechnology
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• v.19 no.10
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• pp.1191-1196
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• 2009

The production of Streptomyces griseus trypsin (SGT) by S. griseus IFO13350 transformed with the expression vector pWHM3-TR1R2, containing sprT encoding SGT and the two positive regulatory genes sgtR1 and sgtR2, was investigated in various media. Cultivation in Ferm-0 gave 1.4 times more trypsin activity than in C5/L medium. In addition, replacement of 2% glucose and 1% skim milk in Ferm-0 with 2% dextrin and 1% tryptone (designated Ferm-II) enhanced trypsin activity 4.1-fold. To simplify the purification process, the supernatant from the S. griseus transformant cultured in Ferm-II medium was fractionated with ammonium sulfate (25-55%), then subjected to Hitrap Benzamidine FF affinity column chromatography. The specific activity of SGT purified by one-step chromatography was 69,550 unit/mg protein and the overall purification yield was above 8%, indicating that this method is more effective than those previously reported. Purified SGT was most active at pH 8.0 and $50^{\circ}C$, and it maintained activity between pH 7.0 and 9.0 and at temperatures up to $70^{\circ}C$. These enzymatic properties are very similar to those of authentic eukaryotic trypsin purified from bovine pancreas.

• Journal of Korean Society on Water Environment
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• v.22 no.2
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• pp.222-229
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• 2006

The treatment performance and operational parameters of a tertiary wastewater treatment process a biological filtration system were investigated. The biological filtration system consisted of a nitrification filter (Fiter 1) and a polishing filter with anoxic and aerobic parts (Filter 2). SS, T-C-BOD, and T-N in effluent were kept stable at less than 3, 5 mg/L, and 5 mgN/L, respectively, under a HRT in Filter (filter-bed) of 0.37~2.3 h. T-N at the outlet of Filter 2 were about 1~5 mgN/L under the condition of LV of 50~202 m/d. In Filter 2, denitrification was accomplished under LV of 50~168 m/d in a 1 m filter-bed. However, the denitrification capacity reached the maximum when the linear velocity was increased to 202 m/d. Relationship between increase in microorganism and headloss was clearer in Filter 2. As a result, the denitrification rate increased from 1.0~2.3 kgN/($m^3-filter-bed{\cdot}d$) as the headloss increased. The COD removal rate was 6.0~9.6 kgCOD/($m^3-filter-bed{\cdot}d$) when operated with Filters 1 and 2. These results mean that captured bacteria contributed a part of COD consumption and denitrification. The maximum nitrification and denitrification rate was 0.5 and 4 kgN/($m^3-filter-bed{\cdot}d$) in Filter 1 and 2.The ratio of backwashing water to the treated water was about 5~10 %. In Filter 1, wasted sludge in backwashing was only 0.7~5.3 gSS/($m^3$-treated water). In Filter 2, added methanol was converted into sludge and its value was 8.0~24 gSS/($m^3$-treated water). These results proved that this process is both convenient to install as tertiary treatment and cost effective to build and operate.

• Journal of Biomedical Engineering Research
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• v.20 no.2
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• pp.213-220
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• 1999

In this study, we measured the absorption coefficient of the tissues of mouse (brain, heart, liver, muscle and tumor) and human brain (normal and tumor) in the wavelength between 500nm~900nm. The optical coefficient is a representative of the characteristics of the materials. So, we can characterize the biological tissue with the optical coefficients. Using the spectrograph monometer and PDA(Photo Diode Array), we experimented with quick-frozen sectioned specimens. Because the optical coefficient is concerned with the conformation and biochemical component of the biological tissue, we experimented as the wavelength between 500nm~900nm on the normal and tumor samples of the animal and human. For the mouse, there are distinctive differences of the absorption coefficients between normal tissues and tumor. The absorption coefficient of the normal tissue varies 0.1~0.2cm$^{-1}$ with wavelength. But, the absorption coefficient of the brain tumor is changed round about 0.4~0.5cm$^{-1}$ as the wavelength. The absorption coefficients we measured can be a useful implement to detect diseases.