• Communications for Statistical Applications and Methods
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• v.12 no.1
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• pp.139-147
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• 2005

It is interesting to locate homogeneous segments within a DNA sequence. Suppose that the DNA sequence has segments within which the observations follow the same residue frequency distribution, and between which observations have different distributions. In this setting, change points correspond to the end points of these segments. This article explores the use of a binary segmentation procedure in detecting the change points in the DNA sequence. The change points are determined using a sequence of nested hypothesis tests of whether a change point exists. At each test, we compare no change-point model with a single change-point model by using the Bayesian information criterion. Thus, the method circumvents the computational complexity one would normally face in problems with an unknown number of change points. We illustrate the procedure by analyzing the genome of the bacteriophage lambda.

• Proceedings of the Korean Biophysical Society Conference
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• 2001.06a
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• pp.31-31
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• 2001

The native strain of serpins (serine protease inhibitors) has been recognized as a mechanism of biological regulation. Indeed, some stabilizing single residue mutations of human $\alpha$$_1$-antitrypsin, a prototype serpin, relieved local strain and caused the loss of inhibitory activity. The native strain of $\alpha$$_1$-antitrypsin is distributed throughout the whole molecule, but the strain that regulates the function directly is highly localized in the regions that appear to be mobilized during complex formation with a target protease.(omitted)

• Applied Biological Chemistry
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• v.8
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• pp.95-100
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• 1967

A quantitative study on the mercury residue in the brown rice of "Paldal", a recommended rice variety in Korea, was carried out by changing the date and frequency of application with different forms of organo-mercury fungicide(PMA), which is used for the control of rice blast. The results are summarized follows: 1) Mercury residues were higher with the emulsion formulation(0.21 ppm) than the dust formulation (0.16 ppm) when they were used for the control of leaf blast on July 13. 2) In case when both of the emulsion and dust formulations were used on July 13 and August 13, respectively, the mrecury residues were lower in the treatment on July 13 (0.216 and 0.16 ppm) than in the treatment on August 13 (0.304 and 0.238 ppm). 3) In an emulsion formulation was applied once on August 13, the mercury residue was 0.304 ppm and its application in twice on July 13 and August 13, the residue was counted 0.32 ppm. In case of dust formulation, the residues were observed 0.238 ppm in a single dose and 0.276 ppm in double application. 4) When the fungicide was applied to the rice plant on August 13, the mercury residues in brown rice, rice bran, and stalk and leaves were 0.304, 0.323, and 0.676 ppm, respectively found in the case of emulsion and in the case of dust formulation, they were 0.238, 0.283 and 0.698 ppm, respectively. The mercury residue, in general, were less in the case of dust than in the case of emulsion formulation and lowered by a single treatment than by two times application and it was also less by treating on July 13 than by treating on August 13.

• Journal of the Korea Organic Resources Recycling Association
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• v.26 no.2
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• pp.75-84
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• 2018

In this study, the analysis of torrefaction products was carried out for fueling of sewage sludge. The mixed samples were composed as follows : 50% of sewage sludge and 50% of rice husk and CR(Coffee Residue). In this experiment, the reaction time(30min, 60min) and temperature($200^{\circ}C$, $250^{\circ}C$, $300^{\circ}C$) were expressed as a single variable using SF(Severity Factor). As a result, it was confirmed that as the SF increased, the heating value and fuel ratio increased, but the CI(Combustibility Index) decreased. The heating value was similarly increased as CR(Coffee Residue) and SF increased. The fuel ratio range of mixed samples was equal to that of lignite(0.5~1.0) in case of SF lower than 6.19 and that of bituminous coal(1.0~1.8) in case of SF higher than 7.36 or above. The CI showed a stable range(3,000~5,500kcal/kg) in low SF as the content of mixed samples contained more rice husk than CR.

• The Korean Journal of Pesticide Science
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• v.14 no.4
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• pp.371-380
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• 2010

This study was performed to develop a precise single residue analytical method of fungicide cyprodinil in representative crops for using as general residue analytical methods which could be applied to most of crops. Apple, mandarin, Korean cabbage and green pepper were selected as representative crops, and they were macerated, extracted with acetonitrile, concentrated and partitioned with n-hexane. Then the extracts were concentrated and cleaned-up through silica gel column with ethyl acetate:n-hexane (15:85, v/v) before concentration and analysis with HPLC. LOQ (limit of quantitation) of cyprodinil was 5 ng (S/N>10) and MQL (method qnantitation limit) was 0.05 mg/kg. Recoveries were measured at three fortification levels (MQL, 10MQL and 100MQL) on crop samples and ranged from 82.0 to 108.2% and coefficients of variation were less than 10% regardless of sample type.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.642-642
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• 2013

Graphene, two dimensional single layer of carbon atoms, has tremendous attention due to its superior property such as high electron mobility, high thermal conductivity and optical transparency. Especially, chemical vapor deposition (CVD) grown graphene has been used as a promising material for high quality and large-scale graphene film. Unfortunately, although CVD-grown graphene has strong advantages, application of the CVD-grown graphene is limited due to ineffective transfer process that delivers the graphene onto a desired substrate by using polymer support layer such as PMMA(polymethyl methacrylate). The transferred CVD-grown graphene has serious drawback due to remaining polymeric residues generated during transfer process, which induces the poor physical and electrical characteristics by a p-doping effect and impurity scattering. To solve such issue incurred during polymer transfer process of CVD-grown graphene, various approaches including thermal annealing, chemical cleaning, mechanical cleaning have been tried but were not successful in getting rid of polymeric residues. On the other hand, lithographical patterning of graphene is an essential step in any form of microelectronic processing and most of conventional lithographic techniques employ photoresist for the definition of graphene patterns on substrates. But, application of photoresist is undesirable because of the presence of residual polymers that contaminate the graphene surface consistent with the effects generated during transfer process. Therefore, in order to fully utilize the excellent properties of CVD-grown graphene, new approach of transfer and patterning techniques which can avoid polymeric residue problem needs to be developed. In this work, we carried out transfer and patterning process simultaneously with no polymeric residue by using a metal etch mask. The patterned thin gold layer was deposited on CVD-grown graphene instead of photoresists in order to make much cleaner and smoother surface and then transferred onto a desired substrate with PMMA, which does not directly contact with graphene surface. We compare the surface properties and patterning morphology of graphene by scanning electron microscopy (SEM), atomic force microscopy(AFM) and Raman spectroscopy. Comparison with the effect of residual polymer and metal on performance of graphene FET will be discussed.

• Journal of Environmental Impact Assessment
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• v.24 no.1
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• pp.1-15
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• 2015

To mitigate the impacts of climate change on agricultural ecosystems, development of agricultural management for enhanced soil carbon sequestration is required. In this study, the effects of fertilizer types (chemical fertilizer and manure compost), cropping systems, and crop residue management on SOC(Soil Organic Carbon) sequestration were investigated. Summer corn and winter barley were cultivated on experimental plots under natural rainfall conditions for two years with chemical fertilizer and manure compost. Soil samples were collected conducted and analyzed for SOC for soil. To estimate long-term variation patterns of SOC, DNDC was run with the experimental data and the weather input parameters from 1981 to 2010. DNDC simulation demonstrated SOC reduction by chemical fertilizer treatment unless plant residues are returned; whereas compost treatments increased SOC under the same conditions and SOC increment was proportional to compost application rate. In addition, SOC further increased under corn-barley cropping system over single corn cropping due to more compost application. Regardless of nutrient input type, residue return increased SOC; however, the magnitude of SOC increase by residue return was lower than by compost application.

• The Korean Journal of Pesticide Science
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• v.13 no.4
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• pp.223-231
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• 2009

This study was performed to develop a precise single residue analytical method of fungicide fenhexamid in representative crops for general residue analytical method which could be applied to most of crops. Korean cabbage, mandarin, apple and green pepper were selected, macerated, extracted with acetone, concentrated and partitioned with dichloromethane. Then the extracts were concentrated and cleaned-up through Florisil column with ethyl acetate/0.1% acetic acid in hexane [15:85, (v/v)] before concentration and analysis with HPLC. LOQ (Limit of Quantitation) of fenhexamid was 1 ng (S/N>10) and MQL (Method Quantitative Limit) was 0.01 mg/kg. Recoveries were measured at two fortification levels (10 MQL and 50 MQL) on crop samples and ranged from 85.2% to 94.8% (mean recoveries) and coefficients of variation were <10% regardless of sample type.

• IMMUNE NETWORK
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• v.3 no.2
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• pp.126-135
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• 2003

Background: One of the important factors in the prognosis of chronic hepatitis B patient is the degree of replication of hepatitis B virus (HBV). It has been known that HBV DNA polymerase plays the essential role in the replication of HBV. HBV DNA polymerase is composed of four domains, TP (Terminal protein), spacer, RT (Reverse transcriptase) and RNaseH. Among these domains, tyrosine, the $65^{th}$ residue of TP is an important residue in protein-priming reaction that initiates reverse transcription. If monoclonal antibody that recognizes around tyrosine residue were selected, it could be applied to further study of HBV replication. Methods: To produce TP-specific scFv (single-chain Fv) by phage display, mice were immunized using synthetic TP-peptide contains $57{\sim}80^{th}$ amino acid residues of TP domain. After isolation of mRNA of heavy-variable region ($V_H$) and light-chain variable region ($V_L$) from the spleen of the immunized mouse, DNA of $V_H$ and $V_L$ were obtained by RT-PCR and joined by a DNA linker encoding peptide (Gly4Ser)3 as a scFv DNA fragments. ScFv DNA fragments were cloned into a phagemid vector. scFv was expressed in E.coli TG1 as a fusion protein with E tag and phage gIII. To select the scFv that has specific affinity to TP-peptide from the phage-antibody library, we used two cycles of panning and colony lift assay. Results: The TP-peptide-specific scFv was isolated by selection process using TP-peptide as an antigen. Selected scFv had 30 kDa of protein size and its nucleotide sequences were analyzed. Indirect- and competitive-ELISA revealed that the selected scFv specifically recognized both TP-peptide and the HBV DNA polymerase. Conclusion: The scFv that recognizes the TP domain of the HBV DNA polymerase was isolated by phage display.

• Microbiology and Biotechnology Letters
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• v.20 no.5
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• pp.551-558
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• 1992

The extracellular endoinulase from Streptomyces sp. 556 was purified and characterized, The culture broth was fractionated by ammonium sulfate saturation followed by DEAE-cellulose column chromatography and 5ephadex G-200 gel filtration, The ultimately purified fraction revealed a single band in 7.5% polyacrylamide gel electropherogram. The purified enzyme showed the maximal activity at pH 5.5-6.0 and $50^{\circ}C$, but lost 93% of inulase activity after 30 min incubation at $55^{\circ}C$ . The essen.tial amino acid residue for catalytic activity appeared to be tryptophan. This endo inulase was activated by $Mn^{2+}$, whereas inactivated by $Ag^{+}$, $Hg^{+}$, $Cu^{2+}$, $Zn^{2+}$, $Fe^{3+}$ and $Mo^{6+}$ EDTA and 8-hydroxyquinoline inhibited the enzyme so that the enzyme was considered to be a metalloenzyme. The Km value for inulin was 0.287 mM, and no invertase or $\alpha$-glucosidase activity was found in the enzyme.