• Food Science of Animal Resources
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• v.25 no.2
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• pp.218-225
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• 2005

This study was performed to determine sequence variation and RFLP of the mt DNA D-loop region using Southern blot hybridization analysis and to develop mt DNA marker affecting milk production traits in Hanwoo cows. The PCR was used to amplify an 1142 bp fragment within the D-loop region of mt DNA using specific primers. Mt DNA were digested with seven restriction enzymes and hybridized using DIG-labeled D-loop probe. The mt DNA RFLP polymorphisms were observed in the four enzymes, BamHI, RsaI, XbaI and HpaII. Nucleotide substitutions were detected at positions 441 (G/C), 469 (T/C), 503 (C/T), 569 (G/A), 614 (C/A) and 644 (C/T) of the mt DNA D-loop region between two selected lines. Significant relationship between the XbaI RFLP type and breeding value was found(p<0.05). Cows with A type had higher estimated breeding values than those with B type (P<0.05) between high and low milk production lines. Therefore, the RFLP marker of mt DNA could be used as a selection assisted tool for individuals with high milk producing ability in Hanwoo.

• Restorative Dentistry and Endodontics
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• v.31 no.1
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• pp.58-65
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• 2006

The possibility of applying a hi-axial flexure strength test on composite resin was examined using three point and hi-axial flexure strength tests to measure the strength of the light-cured resin and to compare the relative reliability using the Weibull modulus. The materials used in this study were light-curing restorative materials, $MICRONEW^{TM},\;RENEW^{(R)}$ (Bisco, Schaumburg, USA). The hi-axial flexure strength measurements used the piston-on-3-ball test according to the regulations of the International Organization for Standardization (ISO) 6872 and were divided into 6 groups, where the radius of the specimens were 12mm (radius connecting the 3-balls: 3.75mm), 16 mm(radius connecting the 3-balls: 5mm), and the thickness were 0.5mm, 1mm, 2mn for each radius. The hi-axial flexure strength of the $MICRONEW^{TM}\;and\;RENEW^{(R)}$ were higher than the three point flexure strength and the Weibull modulus value were also higher in all of the bi-axial flexure strength groups, indicating that the hi-axial strength test is relatively less affected by experimental error. In addition, the 2 mm thick specimens had the highest Weibull modulus values in the hi-axial flexure strength test, and the $MICRONEW^{TM}$ group showed no significant statistical difference (p>0.05). Besides the 2mm $MICRONEW^{TM}$ group, each group showed significant statistical differences (p<0.05) according to the thickness of the specimen and the radius connecting the 3-balls. The results indicate that for the 2mm group, the hi-axial flexure strength test is a more reliable testing method than the three point flexure strength test.

• International Journal of Aeronautical and Space Sciences
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• v.17 no.3
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• pp.352-357
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• 2016

An investigation of ribbed divergent channel was undertaken to determine the effect of rib pitch to height ratio on total friction factor and heat transfer results in the fully developed regime. The ribbed divergent rectangular channel with the channel exit hydraulic diameter ($D_{ho}$) to inlet channel hydraulic diameter ($D_{hi}$) ratio of 1.16 with wall inclination angle of 0.72 deg, at which the ratios (p/e) of 6,10, and 14 are considered. The ribbed straight channel of $D_{ho}/D_{hi}=1.0$ were also used. The ribbed divergent wall is manufactured with a fixed rib height (e) of 10 mm and the ratio of rib spacing (p) to height 6, 10, and 14. The measurement was run with range of Reynolds numbers from 24,000 to 84,000. The comparison shows that the ratio of p/e=6 has the greatest thermal performance in the divergent channel under two constraints; identical mass flow rate and identical pressure drop.

• Mycobiology
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• v.31 no.1
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• pp.32-35
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• 2003

Restriction enzyme-mediated integration(REMI) was used to transform uracil auxotrophs of Pleurotus ostreatus to prototrophy. When protoplasts of Pleurotus ostreatus were treated by the reaction mixture containing 10 units of BamHI, the frequency of REMI was about 64 transformants per 1 ${\mu}g$ of DNA. This efficiency was increased by 14.2 times compared with that of the conventional PEG transformation. The optimal condition for REMI of P. ostreatus was achieved when 1 ${\mu}g$ of linearized pTRura3-2 DNA was added into $1{\times}10^7$ protoplasts along with 10 units BamHI. Southern blot analysis revealed that about 50% of transformants examined were caused by REMI event and 30% carried single copy insertion at the genome. This suggested that the REMI method might be a useful tool for efficient transformation and tagging mutagenesis of P. ostreatus.

• Journal of Veterinary Clinics
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• v.29 no.2
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• pp.124-129
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• 2012

The purpose of this study was to identify the effect of age and gender on the value of electroretinogram (ERG) in healthy dogs. The ERG responses of 68 eyes of 34 dogs (22 males, 12 females) were recorded following the diagnostic protocol for dogs recommended by International Society for Clinical Electrophysiology of Vision under general anesthesia using medetomidine and tiletamine-zolazepam combination. There were significant differences in the implicit time of a-wave of Hi-int R & C response among age groups (P < 0.05) and in the implicit time of a-wave of cone response between male and female (P < 0.05). The rest ERG responses seem to be not affected by age and gender of healthy dogs.

• Journal of Microbiology
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• v.43 no.6
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• pp.503-509
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• 2005

The production of manganese peroxidase (MnP) by Irpex lacteus, purified to electrophoretic homogeneity by acetone precipitation, HiPrep Q and HiPrep Sephacryl S-200 chromatography, was shown to correlate with the decolorization of textile industry wastewater. The MnP was purified 11.0-fold, with an overall yield of $24.3\%$. The molecular mass of the native enzyme, as determined by gel filtration chromatography, was about 53 kDa. The enzyme was shown to have a molecular mass of 53.2 and 38.3 kDa on SDS-PAGE and MALDI-TOF mass spectrometry, respectively, and an isoelectric point of about 3.7. The enzyme was optimally active at pH 6.0 and between 30 and $40^{\circ}C$. The enzyme efficiently catalyzed the decolorization of various artificial dyes and oxidized Mn (II) to Mn (III) in the presence of $H_2O_2$. The absorption spectrum of the enzyme exhibited maxima at 407, 500, and 640 nm. The amino acid sequence of the three tryptic peptides was analyzed by ESI Q- TOF MS/MS spectrometry, and showed low similarity to those of the extracellular peroxidases of other white-rot basidiomycetes.

• Restorative Dentistry and Endodontics
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• v.25 no.3
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• pp.446-458
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• 2000

In this study, compressive strengths of three condensable composite resins(ALERT, SureFil, Solitaire), conventional hybrid composite resin(Z-100) and amalgam(HI-Aristaloy 21) according to the 6 types of cavity design(cylinder, trapezoidal, butt-joint, round bevel, long bevel and short bevel) were measured and appearance of fracture surfaces were observed with SEM, thus evaluated clinical applications of condensable composite resins according to the cavity designs. The results were as follows; 1. Compressive strengths according to experimental materials were the highest in SureFil, and Z-100, ALERT, Solitaire, HI-Aristaloy 21 in order. 2. SureFil showed the highest compressive strength(p<0.05). compressive strengths of ALERT and Solitaire were lower than that of Z-100, hybrid composite(p<0.05). 3. Compressive strengths according to specimen design were the highest in trapezoidal shape(p<0.05) and no significant difference was detected between other specimen designs. 4. The appearance of condensable composite resin under SEM was of a diverse configuration according to component of resin matrix, shapes of filler and surface treatments between resin and filler.

• Microbiology and Biotechnology Letters
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• v.18 no.1
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• pp.98-102
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• 1990

A strain of Erwinia spp. was selected from the soil for the production of bacteriocin to the root rot plant pathogen. Bacteriocin producing gene was not located on plasmid but on chromosome. Genomic library of Erwinia spp. were made by using pLAFR 3 as a vector system for cloning of the gene. It was been cloned and expressed in E. coli DH 5 . Bacteriocin producing colony was composed of pLAFR 3 vector and 3.0 kb EcoRI fragment of Erwinia spp. ehromosomal DNA. The inserted fragment (3.0 kb) was possessed a EcoRI and BarnHI restriction sites.

• Journal of Microbiology
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• v.37 no.2
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• pp.102-110
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• 1999

Genetic determinant for the secondary metabolism was studied in heterologous expression in Streptomyces lividans TK-24 using Streptomyces griseus ATCC 10137 as a donor strain. Chromosomal DNA of S. griseus was ligated into the high-copy number Streptomyces shuttle plasmid, pWHM3, and introduced into S. lividans TK-24. A plasmid clone with 4.3-kb BamHI DNA of S. griseus (pMJJ201) was isolated by detecting for stimulatory effect on actinorhodin production by visual inspection. The 4.3-kb BamHI DNA was cloned into pWHM3 under the control of the strong constitutive ermEp promoter in both directions (pMJJ202); ermEp promoter-mediated transcription for coding sequence reading right to left: pMJJ203; ermEp promoter-mediated transcription for coding sequence reading left to right) and reintroduced into S. lividans TK-24. The production of actinorhodin was markedly stimulated due to introduction of pMJJ202 on regeneration agar. The introduction of pMJJ202 also stimulated production of actinorhodin and undecylproidigiosin in submerged culture employing the actinorhodin production medium. Introduction of pMJJ203 resulted in a marked decrease of production of the two pigments. Nucleotide sequence analysis of the 4.3-kb region revealed three coding sequences: two coding sequences reading left to right, ORF1 and ORF2, one coding sequence reading right to left, ORF3. Therefore, it was suggested that the ORF3 product was responsible for the stimulation of antibiotic production. The C-terminal region of ORF3 product showed a local alignment with Myb-related transcriptional factors, which implicated that the ORF3 product might be a novel DNA-binding protein related to the regulation of secondary metabolism in Streptomyces.

• Korean Journal of Microbiology
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• v.35 no.1
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• pp.13-17
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• 1999

Shigella sonnez is important causes of human enleric infcctions. S. sonnei KNIH104S was isolated from patient of shigellosis in Korea and previously reported. We cloned 1.7 kb BamHI fragment containing the asd gene encoding an aspartate $\beta$-semialdehyde dehydrogenase from chromosomal DNA of S. sonnei KNIH104S. This recombinant plasmid was named as pSAB17. E. coli $\chi$6097, an a d mutant, cannol grow on the LB medium without DL-$\alpha$, $\varepsilon$-diaminopimclic acid (50 pgiml) but E. coli x 6097(pSAB17) can grow on the same medium. We sequenccd the asd gene ol Shigella for the first time. The asd gcne was composed of 1,104 base pairs with ATG initiation codon and TAA termination codon. Sequence comparison of the asd gene exhibited 99.9% nucleolide sequence hornology with that of E. coli. Also, We constructed the balanced-lethal vector using pBluescrip SK(+) and asd gene of S. sonnei KNIH104S.