• Journal of Astronomy and Space Sciences
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• v.28 no.1
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• pp.13-16
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• 2011

The $CH_3OH$ $4_2-5_1$ E transition was observed toward the Sgr B2 region, including the Principal Cloud and its surroundings. This methanol transition shows an extended emission along the 2'N cloud, which is believed to be colliding with the Principal Cloud and may trigger the massive star formation in this cloud. This extended methanol emission may also suggest that the 2'N cloud is under shocks. We derive total methanol column density $N(CH_3OH)\;=\;2.9{\pm}0.3{\times}10^{14}\;cm^{-2}$ toward the peak position of the extended emission. The fractional abundance of methanol is about 10.9, relative to the estimated total $H_2$ abundance, which is similar to the methanol abundances in quiet gas phase.

• Journal of Microbiology and Biotechnology
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• v.2 no.3
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• pp.174-182
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• 1992

The hemagglutinin-esterase glycoprotein (HE) gene of bovine coronavirus, coupled with a simian virus 40 early promoter and polyadenylation signal, was inserted into a human adenovirus transfer vector. The transfer vector was used to co-transfect 293 cells along with adenovirus genomic DNA. The hemagglutinin-esterase transcription unit was rescued into the adenovirus genome by homologous in vivo DNA recombination between the vector plasmid DNA and the adenovirus genomic DNA, and a recombinant adenovirus was isolated by several rounds of plaque assays. Thus the recombinant adenovirus carries the hemagglutinin-esterase gene in the early transcription region 3 (E3) of the adenovirus genome in the parallel orientation to the E3 transcription. The recombinant adenovirus synthesized the HE polypeptide in HeLa cells as demonstrated by immunoprecipitation with anti-coronavirus rabbit antisera. The recombinant HE polypeptide could be labelled by $[^3H]$glucosamine, demonstrating that the recombinant HE was glycosylated. Cells expressing the HE polypeptide exhibited hemadsorption activity when incubated with mouse erythrocytes. The HE was transported to the plasma membrane as shown by the cell surface immunofluorescence, indicating that the recombinant HE polypeptide retained its biological activities. Potential for the use of infectious recombinant adenovirus as a live virus-vectored vaccine candidate for bovine coronavirus disease is discussed.

• Animal Systematics, Evolution and Diversity
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• v.20 no.2
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• pp.99-107
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• 2004

Two epistylid ciliates collected from the sewage treatment plant in Ulsan, Korea were identified as Epistylis chrysemydis Bishop and Jahn, 1941 and E. entzii Stiller, 1935. They were examined in vivo using Die microscope. Protargol impregnation used to reveal the infraciliature and cytological details. The improved diagnoses for these species are as followings. E. chrysemydis: peristomial lip has two bulges encircling the oral region and ciliary rows wound about one and half around peristome; one contractile vacuole located ventrally; stalk ramified hollow; membrane lies 1 and 3 are longer than membranelle 2. E. entzii: peristomial lip has one bulge encircling the oral region and ciliary rows wound about 1 and 1/4 to 1 and 1/3 around peristome; one contractile vacuole located dorsally; stalk ramified, not hollow; membrane lies 1 and 2 are longer than membranelle 3. They are new to Korean fauna.

• Journal of the Korean Society of Radiology
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• v.7 no.3
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• pp.245-249
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• 2013

Neutron sources from photonuclear reaction with 46-MeV electron linear accelerator at Research Reactor Institute, Kyoto University used for resonance energy measurement of natural tantalum. BGO($Bi_4Ge_3O_{12}$) scintillation detectors used for measurement of the prompt gamma ray from the natural tantalum sample. The BGO spectrometer was composed geometrically as total energy absorption detector. The electric signal from the spectrometer was analyzed for TOF(Time-of-Flight) spectrum which is used identification of neutron capture resonance energy. In this study, the neutron energy region is from 1 to 200 eV, because of strong X-ray effect produced photonuclear reaction in Ta target, the measurement was performed to below 1 keV energy region. The resonance energy was compared with the evaluated values(ENDF/B-VI, Mughabghab). All of the resonances from 4.28 ~ 200 eV were seen in the present measurement except 144.3 eV resonance.

• Journal of the Korean Ceramic Society
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• v.29 no.4
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• pp.283-292
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• 1992

Duplex composites such as Y-TZP/Y-TZP-20 wt.% Al2O3 and Y-TZP/Y-TZP- 40 wt.% Al2O3 were made by mixing the sieve-shaked granules followed by isostatic pressing and sintering at 150$0^{\circ}C$ for 1 hour. So Y-TZP became matrix region and Y-TZP-20 wt.% Al2O3 or Y-TZP-40 wt.% Al2O3 became dispersed regions. In these composites, propagating cracks due to thermal shock always run into the dispersed region because these regions act as compressive zone due to low thermal expansion than matrix region. So duplexes having dispersed regions of Y-TZP-40 wt.% Al2O3 showed higher retained strength after thermal shock than matrix only composites because crack propagations were stopped more or less in the dispersed region. But when crack propagations were much more easy than matrix like Y-TZP-20 wt.% Al2O3 region, retained strength was decreased than the matrix only composites despite of the low initial strength.

• Molecules and Cells
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• v.25 no.1
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• pp.30-42
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• 2008

The disease-specific (dsp) region and the hypersensitive response and pathogenicity (hrp) genes, including the hrpW, $hrpN_{Ep}$, and hrpC operons have previously been sequenced in Erwinia pyrifoliae WT3 [Shrestha et al. (2005a)]. In this study, the remaining hrp genes, including the hrpC, hrpA, hrpS, hrpXY, hrpL and hrpJ operons, were determined. The hrp genes cluster (ca. 38 kb) was comprised of eight transcriptional units and contained nine hrc (hrp conserved) genes. The genetic organization of the hrp/hrc genes and their orientation for the transcriptions were also similar to and collinear with those of E. amylovora, showing ${\geq}80%$ homologies. However, ORFU1 and ORFU2 of unknown functions, present between the hrpA and hrpS operons of E. amylovora, were absent in E. pyrifoliae. To determine the HR active domains, several proteins were prepared from truncated fragments of the N-terminal and the C-terminal regions of $HrpN_{Ep}$ protein of E. pyrifoliae. The proteins prepared from the N-terminal region elicited HR, but not from those of the C-terminal region indicating that HR active domains are located in only N-terminal region of the $HrpN_{Ep}$ protein. Two synthetic oligopeptides produced HR on tobacco confirming presence of two HR active domains in the $HrpN_{Ep}$. The HR positive N-terminal fragment ($HN{\Delta}C187$) was further narrowed down by deleting C-terminal amino acids and internal amino acids to investigate whether amino acid insertion region have role in faster and stronger HR activity in $HrpN_{Ep}$ than $HrpN_{Ea}$. The $HrpN_{Ep}$ mutant proteins $HN{\Delta}C187$ (D1AIR), $HN{\Delta}C187$ (D2AIR) and $HN{\Delta}C187$ (DM41) retained similar HR activation to that of wild-type $HrpN_{Ep}$. However, the $HrpN_{Ep}$ mutant protein $HN{\Delta}C187$ (D3AIR) lacking third amino acid insertion region (102 to 113 aa) reduced HR when compared to that of wild-type $HrpN_{Ep}$. Reduction in HR elicitation could not be observed when single amino acids at different positions were substituted at third amino acids insertion region. But, substitution of amino acids at L103R, L106K and L110R showed reduction in HR activity on tobacco suggesting their importance in activation of HR faster in the $HrpN_{Ep}$ although it requires further detailed analysis.

• Korean Journal of Microbiology
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• v.30 no.1
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• pp.60-64
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• 1992

The secretion vector with promoter and signal sequence region of neutral protease gene (npr) from Bacillus amyloliquefaciens was constructed by the technique of polymerase chain reaction (PCR). A unique restriction iste was introduced into the 3' of the signal coding region by the synthesis of PCR primer. To demonstrate the function of cloned promoter and signal sequence, we used the E. coli .betha.-lactamase structural gene as a foreign gene. The signal sequence of .betha.-lactamase gene was deleted by Bal31 exonuclease and only mature region was introduced into the secretion vector. Bacillus subtilis cells transformed by the recombinant vector synthesized the fusion protein and were also capable of removing the signal peptide from the original fusion protein, as judged by the assay of .betha.-lactamase activity and secretion into the growth medium by western blotting.

• Korean Journal of Microbiology
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• v.33 no.2
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• pp.92-96
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• 1997

The 6.8 kb Xhol fragment of chromosomal ONA of Pseudomonas sp. 0177 contains the phnDEFG genes involved in the degradation of polyaromatic hydrocarbons and chlorinated aromatics. Here, we report the nucleotide sequence of the ORF encoding a polypeptide consisted of 143 amino acids with a Mr of 13,859. The nucleotide sequence of the ORF is 99% and 68.6% identical to the downstream region of catE of Sphingomonas sp. strain HV3 and the ORF between xylE and xylG of Sphingomonas yanoikuyae Bl, respectively. The deduced amino acid sequence of the PhnF has 62.3% identity with the amino acid encoded hy orfY region of Citrobacter freundii DSM30040. We now confirm that the ORF is located between the catechol 2,3-dioxygenase (C230), phnE, and 2-hydroxymuconic semialdehyde dehydrogenase (2HMSO), phnG.

• Bulletin of the Korean Chemical Society
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• v.18 no.3
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• pp.296-300
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• 1997

The intracluster ion/molecule reactions within 1,1-difluoroethene homocluster have been studied by electron-impact quadrupole mass spectrometry. When CH2CF2 seeded in helium is expanded and ionized by electron impact, two different types of ion/molecule association (polymerization) reaction products, i.e., (CH2CF2)n+ (n≥l) and (CF2CH2)qX+ (X=fragment species, q≤n), are formed. The higher association products, (CH2CF2)n+ (n=3, 4), have shown stronger intensities over the lower association product, (CH2CF2)2+, in the low electron impact energy region ( < 39 eV). These stronger intensities are interpreted in terms of the stabilization of these ions due to the ring formations over the dimer ion in this energy region. The evidence of ring formation mechanism is on the basis of the intensity distribution of fragments at various electron impact energy. In another typical branched-chain growth reaction of these compounds, the F-shift reaction path is found to be more favorable energetically than the H-shift via the fragment patterns of clusters and semi-empirical calculation.

• The Korean Journal of Mycology
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• v.47 no.3
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• pp.181-186
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• 2019

A designated fungal isolate, KNU-US-1802E was isolated from the soil in Uiseong, Korea. To identify characteristics of the isolate, it was cultured on PDA media for 6 days at $35^{\circ}C$. Colonies on PDA are flat, light gray, dense, with entire margins; reverse dark gray to black, with white margins. Aerial mycelia were smooth-walled, hyaline and 40~42 mm diameter after 6 days at $35^{\circ}C$. Conidia were hyaline, one-celled, ellipsoidal to fusiform, forming long chains with average length ${\times}$ width of $5.0{\pm}0.3{\times}2.9{\pm}0.2{\mu}m$. Molecular analysis indicates that the internal transcribed spacer (ITS) region and partial beta-tubulin (tub2) gene sequence showed 100% and 99% similarities, respectively with Acrophialophora ellipsoidea CGMCC 3.15255 collected from China. Phylogenetic analysis by the neighbor-joining (NJ) method shows that the KNU-US-1802E was clustered with A. ellipsoidea CGMCC 3.15255 in a phylogenetic tree constructed using the concatenated sequences of ITS region and tub2 gene sequences with a high bootstrap value. Based on these findings, the isolate KNU-US-1802E was identified as Acrophialophora ellipsoidea, and this is the first report of this isolate in Korea.