• KSBB Journal
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• v.20 no.4
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• pp.260-265
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• 2005

In this work, molecular imprinted polymers (MIPs) using the template of the N-CBZ (carbobenzyloxy)-L-phenylalanine, MAA and 4-VPY as a monomer, EGDMA as a crosslinker and AIBN as an initiator were considered. The prepared polymer particles $(Ca.\;25-35\;{\mu}m)$ were packed into a chromatographic column $(3.9\;\times\;150\;mm)$. The chromatographic characteristics of the retention on the MIP were experimented with acetonitrile as a mobile phase at the flow rate of mobile phase, 0.5 ml/min. The retention factors and resolutions of chiral racemate of the N-CBZ-D, L-phenylalanine were measured. The results showed that the retention factor and resolution by the two co-monomer imprinting polymer were higher than the single monomer imprinting polymers, which indicated an increase in the affinity of the MIP with the sample as a result of the cooperation effect of the binding sites.

• Journal of Plant Biology
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• v.38 no.2
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• pp.203-209
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• 1995

Tobacco (Nicotiana tahacum L. cv. Wisconsin 38) leaf discs were cocultivated with Agrohacterium carrying a leghemoglobin (Lb) cDNA from Canavalia lineata. Seven plants were regenerated from the transformed leaf discs on MS media supplemented with 0.5 mg/L BAP, 0.1 mg/L ${\alpha}-NAA$, 200 mg/L kanamycin and 500 mg/L carbenicillin. Southern hybridization and PCR of genomic DNA from transgenic plants showed that the Lb cDNA was stably integrated into the genome of the tobacco. Total RNA from the transgenic tobacco showed northern hybridization signal at 1,000 nt and PCR of the first strand cDNA synthesized from the total RNA amplified 0.5 kb Lb cDNA. Furthermore, western hybridization using a polyclonal antibody against soybean Lb showed a 15.8 kD LB-like band on SDS-PAGE of proteins from the transformed tobacco. These results demonstrated that the Lb cDNA of C. lineata was not only incorporated into the genome of tobacco, but also transcribed into mRNA and translated into Lb protein in the transformed tabacco.

• Journal of Korean Society of Steel Construction
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• v.18 no.5
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• pp.535-542
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• 2006

In this study, the effects of cross beams on the lateral distribution of live loads in composite rolled H-beam girder bridges, were investigated through three-dimensional finite element analysis. The parameters considered in this study were the inertial moment ratio between the main girder and the cross beam, the presence of the cross beam, and the number of cross beams. The live load lateral distribution factors were investigated through finite element analysis and the customary grid method. The results show that there was no difference between the bridge models with and without a cross beam. The cross beam of the beam and frame types also showed almost the same live load lateral distribution factors. However, the finite element analysis showed that the concrete slab deck plays a major role in the lateral distribution of a live load, and consequently, the effect of the cross beam is not so insignificant that it can be neglected.

• Journal of Life Science
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• v.24 no.4
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• pp.428-436
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• 2014

Loop-mediated isothermal amplification (LAMP) technique relies on autocycling strand displacement DNA sysnthesis without template denaturation steps under isothermal conditions. LAMP has more advantages than modern PCR, as it requires only basic laboratory equipment like an isothermal water bath, oven, and heating cabinet. Hence, in this study, five random primers were designed with Streptococcus parauberis, shikimate kinase Arok gene sequences (Genbank accession number: CP0024711). Two primers were selected based on the ladder pattern. Other optimum reaction conditions like temperature, time, and sensitivity were established and confirmed with conventional SYBR-green PCR. Results confirmed that the designed random primers were species specific, without any non-target DNA amplification under isothermal conditions. Hence, this study suggests that LAMP techniques could be used in the diagnosis of fish pathogen, specifically S. parauberis.

• Journal of Animal Science and Technology
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• v.46 no.4
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• pp.555-562
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• 2004

본 연구는 목저은 다음과 같다: 1) 돼지에서 150-kDa temary insulin-like growth faetor(IGF)complex의 한 구성 요소인 acid-labile subunit(ALS) 유전자 intron의 존재 확인. cloning 및 돼지 ALS(porcine ALS; pALS) complementary DNA(cDNA)의 3' 비해독(untranslated) 부위(3' UT) 증폭. cloning, 2) intron-spanning primer pair를 이용한 reverse transcription-polymerase chain reaction(RT-PCR) 방법에 의한 돼지 조직에서의 ALS 유전자 발현 분포 확인 및 3) 돼지 hepatocyte에서의 ALS 유전자 발현 여부 확인. 돼지 genomic DNA를 template로 하여 PCR 방법으로 예상된는 intron 부위를 증폭하고 plasmid vector에 삽입하여 염기서열을 결정한 결과 타 종의 ALS 유전자에서와 같은 위치에 1,371-base pair(bp)의 pALS intron이 존재함을 확인하였다. 역시 본 연구에서 간에서 추출한 RNA를 주형으로 시작하여 3' rapid amplification of cDNA end(3' RACE) 방법으로 147-bp의 3'UT를 합성하고 그 염기성열을 결정하였다. RT-PCR 결과 간은 물론 조사된 모든 돼지의 내장기관(신장, 폐, 비장)과 자성 생식기관(난소, 난관, 자궁) 및 골격근육에서 ALS 유전자가 발현됨이 밝혀졌다. 또한 돼지 간 조직에 대한 in-situ hybridization 결과 hepatocyte에서 ALS 유전자가 발현됨이 확인되었다. 이상의 결과는 ALS가 혈중 IGF의 저정/조절체로서의 주기능 외에 모세혈관 밖에서도 미지의 기능이 있을 기능성을 시사한다.

• Elastomers and Composites
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• v.49 no.4
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• pp.330-335
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• 2014

Niobium pentoxide ($Nb_2O_5$) nanoparticles were synthesized using niobium (V) chloride and pluronic F108NF as the precursor and templating agent, respectively. The $Nb_2O_5$-graphene nanocomposites were placed in an electric furnace at $700^{\circ}C$ and calcined under Ar atmosphere for 2 h. The morphology, crystallinity, and photocatalytic degradation activity of the samples were characterized by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and UV-vis spectroscopy. The $Nb_2O_5$-graphene nanocomposites acted as a photocatalyst in the photocatalytic degradation of organic dyes under 254 nm UV light; the organic dyes used were methylene blue (MB), methyl orange (MO), rhodamine B (RhB), and brilliant green (BG). The photocatalytic degradation kinetics for the aforesaid dyes were determined in the presence of the $Nb_2O_5$-graphene nanocomposites.

• Applied Chemistry for Engineering
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• v.31 no.6
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• pp.630-634
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• 2020

We developed a processing recipe to synthesize flexible polyurethane foam with a pore size of 335 ± 107 ㎛. The gelling reaction time was varied from 0 to 30 minutes and the physical properties of the foam were evaluated. The gelling reaction where the polypropylene glycol and tolylene 2,4-diisocyanate (TDI) were reacted to form urethane prepolymer, proceeded until a chemical blowing agent, deionized water, was introduced. Fourier transform infrared (FT-IR) spectra showed that the composition of the foam did not change but the foam height reached a peak value when the gelling reaction time was 10 minutes. We found that increasing the gelling time lessened the coalescence and helped the formation of cells. Lastly, the repeatability of polyurethane foam was confirmed by one-way analysis of variance (ANOVA) by synthesizing ten identical polyurethane foams under the same experimental conditions, including the gelling reaction time. Overall, the new time parameter in-between the gelling and blowing reactions will give extra stability in manufacturing identical polyurethane foams and can be applied to various polyurethane foam processes.

• Korean Journal of Materials Research
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• v.32 no.12
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• pp.545-552
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• 2022

Tin-antimony sulfide nanocomposites were prepared via hydrothermal synthesis and a N₂ reduction process for use as a negative electrode in a sodium ion battery. The electrochemical energy storage performance of the battery was analyzed according to the tin-antimony composition. The optimized sulfides exhibited superior charge/discharge capacity (770 mAh g^-1 at a current density of 100 mA g^-1) and stable lifespan characteristics (71.2 % after 200 cycles at a current density of 500 mA g^-1). It exhibited a reversible characteristic, continuously participating in the charge-discharge process. The improved electrochemical energy storage performance and cycle stability was attributed to the small particle size, by controlling the composition of the tin-antimony sulfide. By optimizing the tin-antimony ratio during the synthesis process, it did not deviate from the solubility limit. Graphene oxide also acts to suppress volume expansion during reversible electrochemical reaction. Based on these results, tin-antimony sulfide is considered a promising anode material for a sodium ion battery used as a medium-to-large energy storage source.

• Composites Research
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• v.21 no.3
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• pp.24-30
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• 2008

Durability problems may arise in the concrete, which is one of the major construction materials, used in the construction field. Bridge piers and foundation piles are usually made with concrete and they are exposed to the moisture and hence the durability of the concrete reduced significantly due to oxidization of re-bar and icing of concrete. To mitigate such problems, FRP tube has been developed and the concrete filled FRP tube (CFFT) has been investigated to find the confinement effect which is provided additionally. It was reported that if the concrete is wrapped with FRP, strength and chemical resistance are improved significantly. In order to apply such a member in the construction field, structural behavior and applicable design guideline or design criteria must be thoroughly investigated. In the experimental investigation, the results are compared with the previous research results and the relationship which can predict the ultimate strength and strain is suggested. In addition, some comments found at the compression tests are given briefly.

• Korean Journal of Remote Sensing
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• v.39 no.6_2
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• pp.1577-1589
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• 2023

Recently, the necessity of predicting changes for monitoring ocean is widely recognized. In this study, we performed a time series prediction of remote-sensing reflectance (Rrs), which can indicate changes in the ocean, using Geostationary Ocean Color Imager (GOCI) data. Using GOCI-I data, we trained a multi-scale Convolutional Long-Short-Term-Memory (ConvLSTM) which is proposed in this study. Validation was conducted using GOCI-II data acquired at different periods from GOCI-I. We compared model performance with the existing ConvLSTM models. The results showed that the proposed model, which considers both spatial and temporal features, outperformed other models in predicting temporal trends of Rrs. We checked the temporal trends of Rrs learned by the model through long-term prediction results. Consequently, we anticipate that it would be available in periodic change detection.