• Food Science of Animal Resources
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• v.29 no.4
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• pp.415-422
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• 2009

In this study, several factors were analyzed in an effort to determine the effects of transglutaminase (TGase) treatment on sodium caseinate (NaCN), ${\alpha}--lactalbumin$ (${\alpha}-La$), and ${\beta}-lactoglobulin$ (${\beta}-Lg$) polymerization reactions. The results of SDSPAGE showed that NaCN was slightly hydrolyzed to molecular weights of 50-400 kDa according to activation time. ${\alpha}-La$ formed high-molecular polymers of 30-300 kDa, whereas ${\beta}-Lg$ remained almost completely unhydrolyzed. Melting temperatures of NaCN, ${\alpha}-La$ with and without TGase were all in the range of $100{\pm}10^{\circ}C$ under the endothermic curve, and the melting temperature of ${\beta}-Lg$ with TGase was lower than that with TGase. When the proteins were incubated for 3 h with TGase, the micrographic structures showed a small quantity of sediment and broad layers. The final ${\alpha}-La$ residues remained at a level of 21.38%, and the TGase-treated ${\alpha}-La$ was confirmed to have undergone a profound loss of mass, to 18.25%. The DPPH-radical scavenging activity of NaCN and ${\beta}-Lg$ with TGase treatment was higher than that observed in the untreated sample, while those of ${\alpha}-La$ increased with concentration.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.5
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• pp.1125-1129
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• 2008

Polypropylene (PP)/corn starch master batch(starch-MB) blends with different PP compositions of 90, 80, 70, and 60 wt% were prepared by melt compounding at $200^{\circ}C$, using lab scale Brabender mixer. The chemical structures, thermal properties and non-isothermal crystallization behavior of the PP/starch-MB blends were investigated by FT-infrared spectrometry (FT-IR), differential scanning calorimetry (DSC), and thermogravimetric analyzer (TGA). The fabrication of the PP/starch-MB blend was confirmed by the existence of hydroxy group in FT-IR spectrum. There was no district change in melting temperature and melting enthalpy, and TGA curve indicates a decrease in degradation temperature with starch-MB content. The non-isothermal crystallization process was analyzed using by Avrami equation. The Avrami exponents were in the range of 2.71-3.97 for PP and 1.48-1.99 for PP/starch-MB blonds. The activation energies calculated by Kissinger method were 233 kJ/mol for PP, 484 kJ/mol for PP90, 541 kJ/mol for PP80, 553 kJ/mol for PP70, and 422 kJ/mol for PP60.

• Korean Journal of Materials Research
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• v.12 no.8
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• pp.617-623
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• 2002

In order to improve the hydrogen storage capacity and the activation properties of the hydrogen storage alloys, the rare-earth metal alloy series, $MmNi_{ 4.5}$$Mn_{0.5}$ $Zr_{x}$ (x=0, 0.025, 0.05, 0.1), are prepared by adding the excess Zr in $MmNi_{4.5}$ $Mn_{0.5}$ / alloy for the strong resistance to intrinsic degradation. The hydrogen storage alloys of rare-earth metal such as $LaNi_{5}$ , and $MmNi_{5}$X and $MmNi_{4.5}$ /$_Mn{0.5}$ alloys which substituted La by misch metal properties were characterized as well. The hydrogen storage alloys were produced by melting each metal mixture in arc melting furnace, and the as-cast alloys were heat-treated at $1100^{\circ}C$ for 10 hr. The major elements of misch metal(Mm) were La, Ce, Pr and Nd with some impurities less than 1wt.% determined by ICP-AES. X-ray diffraction indicated that the structure for these samples was a single phase of hexagonal with $CaCu^{5}$ type. As the Zr contents increases, the activation time and the plateau pressure decrease and sloping of the plateau pressure increase. Amount of the 2nd phases increases with increase in Zr contents in $MmNi_{ 4.5}$$Mn_{0.5}$ $Zr_{0.1}$ alloy, This phenomenon indicated that $ZrNi_3$ in this phase, which shows the maximum storage capacity and the strong resistance to intrinsic degradation, is considered as a proper alloy for hydrogen storage..

• Research in Plant Disease
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• v.18 no.4
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• pp.298-303
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• 2012

Tomato yellow leaf curl virus (TYLCV), transmitted exclusively by the whitefly (Bemisia tabaci) in a circulative manner is one of the most important virus in tomato. Since the first report of TYLCV incidence in Korea in 2008, the virus has rapidly spread nationwide. TYLCV currently causes serious economic losses in tomato production in Korea. Early detection of TYLCV is one of the most important methods to allow rouging of infected tomato plants to minimize the spread of TYLCV disease. We have developed an ultra-rapid and sensitive real-time polymerase chain reaction (PCR) using a new designed real-time PCR system, GenSpectorTM TMC-1000 that is a small and portable real-time PCR machine requiring only a $5{\mu}l$ reaction volume on microchips. The new system provides ultra-high speed reaction (30 cycles in less than 15 minutes) and melting curve analysis for amplified TYLCV products. These results suggest that the short reaction time and ultra sensitivity of the GenSpector$^{TM}$-based real-time PCR technique is suitable for monitoring epidemics and pre-pandemic TYLCV disease. This is the first report for plant virus detection using an ultra-rapid real-time PCR system.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.5
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• pp.1873-1880
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• 2015

Background: A recent genome-wide association study (GWAS) on patients with chronic hepatitis C (CHC) treated with peginterferon and ribavirin (pegIFN-${\alpha}$/RBV) identified a single nucleotide polymorphism (SNP) on chromosome 19 (rs12979860) which was strongly associated with a sustained virological response (SVR). The aim of this study was twofold: to study the relationship between IL28B rs12979860 and sustained virological response (SVR) to pegIFN-${\alpha}$/RVB therapy among CHC patients and to detect the rs12979860 polymorphism by high resolution melting curve (HRM) assay as a simple, fast, sensitive, and inexpensive method. Materials and Methods: The study examined outcomes in 100 patients with chronic hepatitis C in 2 provinces of Iran from December 2011 to June 2013. Two methods were applied to detect IL28B polymorphisms: PCR-sequencing as a gold standard method and HRM as a simple, fast, sensitive, and inexpensive method. Results: The frequencies of IL28B rs12979860 CC, CT, and TT alleles in chronic hepatitis C genotype 1a patients were 10% (10/100), 35% (35/100), and 6% (6/100) and in genotype 3a were 13% (13/100), 31% (31/100), and 5% (5/100), respectively. In genotype 3a infected patients, rs12979860 (CC and CT alleles) and in genotype 1a infected patients (CC allele) were significantly associated with a sustained virological response (SVR). The SVR rates for CC, CT and TT (IL28B rs12979860) were 18%, 34% and 4%, respectively. Multiple logistic regression analysis identified two independent factors that were significantly associated with SVR: IL-28B genotype (rs 12979860 CC vs TT and CT; odds ratio [ORs], 7.86 and 4.084, respectively), and HCV subtype 1a (OR, 7.46). In the present study, an association between SVR rates and IL28B polymorphisms was observed. Conclusions: The HRM assay described herein is rapid, inexpensive, sensitive and accurate for detecting rs12979860 alleles in CHC patients. This method can be readily adopted by any molecular diagnostic laboratory with HRM capability and will be clinically beneficial in predicting treatment response in HCV genotype 1 and 3 infected patients. In addition, it was demonstrated that CC and CT alleles in HCV-3a and the CC allele in HCV-1a were significantly associated with response to pegIFN-${\alpha}$/RBV treatment. The present results may help identify subjects for whom the therapy might be successful.

• Korean Journal of Clinical Laboratory Science
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• v.48 no.2
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• pp.88-93
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• 2016

Dirofilaria immitis is a filarial nematode parasite that causes cardiopulmonary dirofilariasis in dogs. The purpose of this study was the development of real-time PCR assays for efficient detection of D. immitis. The D. immitis-specific primers confirmed in our previous study and a newly designed TaqMan probe were used for quantitative diagnostics. First, SYBR Green real-time PCR was performed using the specific primers and serially diluted genomic DNA or plasmid DNA, and melting curve analyses were performed after amplification. The melting curve showed one specific peak in each of the genomic and plasmid DNA reactions, suggesting that the primers specifically amplify the D. immitis cytochrome c oxidase subunit I gene. Comparison of SYBR Green and TaqMan real-time PCR using serially diluted plasmid DNA showed higher efficiency and specificity with TaqMan real-time PCR. The real-time PCR assays developed in this study will provide improved diagnostic methods to overcome the limitations of conventional diagnostic tools and facilitate more rapid and accurate diagnoses.

• Journal of Plant Biotechnology
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• v.48 no.2
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• pp.71-76
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• 2021

Angelica is a perennial plant used widely for medicinal purposes. Information on the genetic diversity of Angelica populations is important for their conservation and germplasm utilization. Although Angelica is an important medicinal plant genus registered in South Korea, no molecular markers are currently available to distinguish individual species from other similar species in different countries, in particular, China and Japan. In this study, we developed single nucleotide polymorphism (SNP) markers derived from internal transcribed spacer regions of the nuclear ribosomal DNA to identify a distinct domestic species, Angelica gigas Nakai, via a high-resolution melting (HRM) curve analyses. We also performed HRM curve analysis of intentionally mixed genomic DNA samples from five Angelica species. Finally, we investigated A. gigas Nakai and A. sinensis using varying ratios of mixed genomic DNA templates. The SNP markers developed in this study are useful for rapidly identifying A. gigas species from different countries.

• Journal of Plant Biotechnology
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• v.45 no.2
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• pp.102-109
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• 2018

Thistle is a perennial plant that is widely used for medicinal purposes. Information on the genetic diversity of thistle populations are great important for their conservation and germ plasmic utilization. Although thistle is an important medicinal plant species registered in South Korea, no molecular markers are currently available to distinguish them from other similar species from different countries. In this study, we developed single nucleotide polymorphism (SNP) markers derived from the nuclear ribosomal DNA internal transcribed spacer (ITS) regions of genomic sequences to identify distinct Korean-specific thistle species via an amplification refractory mutation system (ARMS)-PCR and high resolution melting (HRM) curve analyses. We performed molecular authentication of four different kinds of thistle species from different regions using DNA sequences in the ITS intergenic region. We also developed a quantitative PCR assay using species-specific ITS primers, which allowed us to estimate the ratio of Korean-specific thistle species using varying ratios of mixed genomic DNA templates from the two species. The SNP markers developed in this study are useful for rapidly identifying specific thistle species from different countries.

• Economic and Environmental Geology
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• v.29 no.4
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• pp.455-470
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• 1996

Mesozoic granitic rocks in the Korean peninsula contain $H_2$, $CH_4$, CO and rare $C_2H_6$. The Jurassic Daebo granites mostly belonging to the ilmenite series are predominated in $CH_4$. Meanwhile, the magnetite series Bulguksa granites of Cretaceous age in the Kyongsang basin and Okchon zone are relatively enriched in $CO_2$. The older granites have a wide variation of $CH_4/CO_2$ ratios (0.1~1.0) compared to those of the younger ones (0.1~0.5). This characteristics of gas compositions suggest that the Jurassic granites are principally derived from the partial melting of metasedimentary rocks with much reducing materials in the lower continental crust. On the other hand, the mantle source granitic magmas might be responsible for the Cretaceous granites characterized by dominant and homogeneous $CO_2$ gas compositions. Liquid-vapor homogenization temperatures of quartz in the Jurassic and Cretaceous granites range from 108 to $539^{\circ}C$ (av. $324^{\circ}C$) and 160 to $556^{\circ}C$ (av. $358^{\circ}C$), respectively. Their salinities are between 0.2 and 16.3 wt.% NaCl for the Jurassic granites and 0.4, and 15.6 wt.% NaCl for the Cretaceous ones. Fluid inclusions with solid daughter minerals lying on or near the halite equilibrium curve represent inclusion fluids from the magmatic stage. The type I and II fluid inclusions which are plotted apart from the equilibrium curve are considered to trap in late hydrothermal alteration stage with a increasing influx of metedric water.

• Journal of the Korean institute of surface engineering
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• v.33 no.2
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• pp.93-100
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• 2000

Effects of Ti content and Ti underlayer on the pitting behavior of TiN coated AISI 304 stainless steel have been studied. The stainless steel containing 0.1~1.0wt% Ti were melted with a vacuum melting furnace and heat treated at $1050^{\circ}C$ for 1hr for solutionization. The specimen were coated with l$\mu\textrm{m}$ and 2$\mu\textrm{m}$ thickness of Ti and TiN by E-beam PVD method. The microstructure and phase analysis were conducted by using XRD, XPS and SEM with these specimen. XRD patterns shows that in TiN single-layer only the TiN (111) Peak is major and the other peaks are very weak, but in Ti/TiN double-layer TiN (220) and TiN (200) peaks are developed. It is observed that the surface of coating is covered with titanium oxide (TiO$_2$) and titanium oxynitride ($TiO_2$N) as well as TiN. Corrosion potential on the anodic polarization curve measured in HCl solution increase in proportion to the Ti content of substrate and by a presence of the Ti underlayer, whereas corrosion and passivation current densities are not affected by either of them. The number and size of pits decrease with increasing Ti content and a presence of the coated Ti film as underlayer in the TiN coated stainless steel.