• Parasites, Hosts and Diseases
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• v.55 no.2
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• pp.149-158
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• 2017

Variant surface antigens (VSAs) encoded by pir families are considered to be the key proteins used by many Plasmodium spp. to escape the host immune system by antigenic variation. This attribute of VSAs is a critical issue in the development of a novel vaccine. In this regard, a population genetic study of vir genes from Plasmodium vivax was performed in the Republic of Korea (ROK). Eighty-five venous blood samples and 4 of the vir genes, namely vir 27, vir 21, vir 12, and vir 4, were selected for study. The number of segregating sites (S), number of haplotypes (H), haplotype diversity (Hd), DNA diversity (${\pi}$ and ${\Theta}_w$), and Tajima's D test value were conducted. Phylogenetic trees of each gene were constructed. The vir 21 (S=143, H=22, Hd=0.827) was the most genetically diverse gene, and the vir 4 (S=6, H=4, Hd=0.556) was the opposite one. Tajima's D values for vir 27 (1.08530, P>0.1), vir 12 (2.89007, P<0.01), and vir 21 (0.40782, P>0.1) were positive, and that of vir 4 (-1.32162, P>0.1) was negative. All phylogenetic trees showed 2 clades with no particular branching according to the geographical differences and cluster. This study is the first survey on the vir genes in ROK, providing information on the genetic level. The sample sequences from vir 4 showed a clear difference to the Sal-1 reference gene sequence, whereas they were very similar to those from Indian isolates.

• Journal of Plant Biology
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• v.38 no.1
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• pp.19-24
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• 1995

The vir genes expression of Ti plasmid is induced by a family of related phenolic compounds. We investigated the effects of various phenolic compounds, Ti plasmids and hosts on the expression of the vir genes in the same type of octopine Ti plasmids, pTiKU12, pTiAch5 and pTiA6. The vir gene induction of pTiKU12 was remarkably stimulated by p-coumaric acid in relation to acetosyringone, but those of pTiAch5 and pTiA6 were more stimulated by acetosyringone than by p-coumaric acid. The effect of phenolic compound on the vir gene induction was different according to the kind of Ti plasmids. Also, the vir gene expression of A. tumefaciens KU913, which has pTiKU12 was about 6.2 times as much as that of A. tumefaciens KU915, which has pTiKU12 in KU12 host, in the presence of ferulic acid. But no difference was shown in the presence of p-coumaric acid. The vir gene induction abilities of phenolic compounds are different according to the kinds of phenolic compounds, Ti plasmids and hosts.

• Parasites, Hosts and Diseases
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• v.52 no.5
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• pp.557-564
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• 2014

The vir genes are antigenic genes and are considered to be possible vaccine targets. Since India is highly endemic to Plasmodium vivax, we sequenced 5 different vir genes and investigated DNA sequence variations in 93 single-clonal P. vivax isolates. High variability was observed in all the 5 vir genes; the vir 1/9 gene was highly diverged across Indian populations. The patterns of genetic diversity do not follow geographical locations, as geographically distant populations were found to be genetically similar. The results in general present complex genetic diversity patterns in India, requiring further in-depth population genetic and functional studies.

• Journal of Astronomy and Space Sciences
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• v.21 no.2
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• pp.83-92
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• 2004

The absolute dimensions of low mass contact binary, GR Vir and HV Aqr were obtained using WD program from the published spectroscopic and photometric observational data. The evolutionary status of this type of system including GR Vir and HV Aqr has been considered. The primary stars of low mass contact binary system were located on the Terminal Age Main-sequence and secondary stars were located under the Zero Age Main-sequence in H-R diagram.

• The Journal of Advanced Prosthodontics
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• v.14 no.6
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• pp.369-378
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• 2022

PURPOSE. The purpose of this in vitro study was to assess whether scanning strategies of virtual interocclusal record (VIR) affect the accuracy of VIR during intraoral scanning. MATERIALS AND METHODS. Five pairs of reference cubes were added to the digital upper and lower dentitions of a volunteer, which were printed into resin casts. Subsequently, the resin casts were articulated in the maximal intercuspal position in a mechanical articulator and scanned with an industrial computed tomography system, of which the VIR was served as a reference VIR. The investigated VIR of the upper and lower jaws of the resin master cast were recorded with an intraoral scanner according to 9 designed scanning strategies. Then, the deviation between the investigated VIRs and reference VIR were analyzed, which were measured by the deviation of the distances of six selected reference points on the upper reference cubes in each digital cast to the XY-plane between the investigated VIRs and reference VIR. RESULTS. For the deviation in the right posterior dentitions, RP group (only scanning of right posterior dentitions) showed the smallest deviation. Besides, BP group (scanning of bilateral posterior dentitions) showed the smallest deviation in the left posterior dentitions. Moreover, LP group (scanning of left posterior dentitions) showed the smallest deviation in the anterior dentitions. For the deviation of full dental arches, BP group showed the smallest deviation. CONCLUSION. Different scanning strategies of VIR can influence the accuracy of alignment of virtual dental casts. Appropriate scanning strategies of VIR should be selected for different regions of interest and edentulous situations.

• Microbiology and Biotechnology Letters
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• v.50 no.2
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• pp.301-309
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• 2022

Helicobacter pylori (H. pylori) establishes infection in the human gastric mucosa for a long time and causes severe gastric diseases such as peptic ulcer and gastric cancer. When H. pylori is exposed to the antibacterial agents or inhibitors, the expression of pathogenic associated genes could be altered. In this study, we analyzed the transcriptional changes of H. pylori genes induced by zerumbone treatment. RNA expression changes were analyzed using next-generation sequencing (NGS), and then reverse transcription-polymerase chain reaction (RT-PCR) was performed to verify the results. As a result of NGS analysis, a total of 23 out of 1,632 genes were differentially expressed by zerumbone treatment. RT-PCR confirmed that zerumbone treatment regulated the expression level of 14 genes. Among the genes associated with DNA replication, transcription, virulence factors and T4SS components, 10 genes (dnaE, dnaQ, rpoA, rpoD, secA, flgE, flhA, virB5, virB8 and virB9) were significantly down-regulated and 4 genes (flaA, flaB, virB4 and virD4) were up-regulated. The results of our current study imply that zerumbone might be a potential therapeutic agent for H. pylori infection by regulating factors related to various H. pylori pathogenicity.

• Proceedings of the Zoological Society Korea Conference
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• 1994.10a
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• pp.247.2-247
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• 1994

No Abstract, See Full Text

• The Journal of the Acoustical Society of Korea
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• v.31 no.6
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• pp.373-383
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• 2012

The performance of underwater acoustic communication system is sensitive to the Doppler shift and ISI(Inter-Symbol Interference). Therefore, the simulation algorithm needs to consider time-spread due to multipath arrivals which cause the ISI, and time-varying Doppler shift along with moving source and receiver. For this purpose, VirTEX(Virtual Time series EXperiment) based on Ray model has been developed. In this paper, VirTEX is used to compare the characteristics of ocean waveguide from the experimental data and illustrate the performance. The CIR(Channel Impulse Response) that characterizes the multipath arrivals with representative time-spread due to multipath arrivals is compared between numerically simulated and experimental probe signal. Also, the communication performance analysis for BER(Bit Error Rate) is compared between numerically simulated and experimental data signal. As a result, VirTEX can be useful as a simulation tool for evaluating the performance of underwater acoustic communication system.

• The Journal of Society for e-Business Studies
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• v.19 no.4
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• pp.31-43
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• 2014

These days a lot of cyber attacks are exploiting the vulnerabilities of S/W. According to the trend of vulnerabilities is announced periodically, security directions are suggested and security controls are updated with this trend. Nevertheless, cyber attacks like hacking during the year 2011 are increased by 81% compared to 2010. About 75% of these cyber attacks are exploiting the vulnerabilities of S/W itself. In this paper, we have suggested a VIR model, which is a spread model of malware infection for measuring economic loss by S/W vulnerability, by applying the SIR model which is a epidemic model. It is applied to estimate economic loss by HWP(Hangul word) S/W vulnerabilities.

• Korean Journal of Remote Sensing
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• v.18 no.6
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• pp.319-326
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• 2002

Rainfall estimation was conducted based on TRMM-PR/VIES and GMS data. AWS rainfall data were used for various validation. General procedure is as follows; 1) Z-R relationship was made by the comparison of TRMM-PR and AWS data. 2) new algorithm was developed by the estimates from Z-R equation and TBB of VIRS. 3) rainfall was estimated through the substitution of GMS data for TBB of VIRS in the newly developed algorithm. Z-R relationship based on TRMM is $Z=303R^{0.72}$ with correlation coefficient 0.57. The newly developed algorithm is shown as correlation coefficient 0.67 and RMSE 17mm/hr. New algorithm shows the underestimating tendency in case of heavy rainfall event.