Bayesian pollution source identification via an inverse physics model

Hwang, Youngdeok,Kim, Hang J.,Chang, Won,Yeo, Kyongmin,Kim, Yongku Elsevier 2019 Computational statistics & data analysis Vol.134 No.-

<P><B>Abstract</B></P> <P>The behavior of air pollution is governed by complex dynamics in which the air quality of a site is affected by the pollutants transported from neighboring locations via physical processes. To estimate the sources of observed pollution, it is crucial to take the atmospheric conditions into account. Traditional approaches to building empirical models use observations, but do not extensively incorporate physical knowledge. Failure to exploit such knowledge can be critically limiting, particularly in situations where near-real-time estimation of a pollution source is necessary. A Bayesian method is proposed to estimate the locations and relative contributions of pollution sources by incorporating both the physical knowledge of fluid dynamics and observed data. The proposed method uses a flexible approach to statistically utilize large-scale data from a numerical weather prediction model while integrating the dynamics of the physical processes into the model. This method is illustrated with a real wind data set.</P>

Phosphoacceptors Threonine 162 and Serines 170 and 178 within the Carboxyl-Terminal RRRS/T Motif of the Hepatitis B Virus Core Protein Make Multiple Contributions to Hepatitis B Virus Replication

Jung, Jaesung,Hwang, Seong Gyu,Chwae, Yong-Joon,Park, Sun,Shin, Ho-Joon,Kim, Kyongmin American Society for Microbiology 2014 Journal of virology Vol.88 No.16

<P>Phosphorylation of serines 157, 164, and 172 within the carboxyl-terminal SPRRR motif of the hepatitis B virus (HBV) core (C) protein modulates HBV replication at multiple stages. Threonine 162 and serines 170 and 178, located within the carboxyl-terminal conserved RRRS/T motif of HBV C protein, have been proposed to be protein kinase A phosphorylation sites. However, <I>in vivo</I> phosphorylation of these residues has never been observed, and their contribution to HBV replication remains unknown. In this study, [<SUP>32</SUP>P]orthophosphate labeling of cells expressing C proteins followed by immunoprecipitation with anti-HBc antibody revealed that threonine 162 and serines 170 and 178 are phosphoacceptor residues. A triple-alanine-substituted mutant, mimicking dephosphorylation of all three residues, drastically decreased pregenomic RNA (pgRNA) encapsidation, thereby decreasing HBV DNA synthesis. In contrast, a triple-glutamate-substituted mutant, mimicking phosphorylation of these residues, decreased DNA synthesis without significantly decreasing encapsidation. Neither triple mutant affected C protein expression or core particle assembly. Individual alanine substitution of threonine 162 significantly decreased minus-strand, plus-strand, and relaxed-circular DNA synthesis, demonstrating that this residue plays multiple roles in HBV DNA synthesis. Double-alanine substitution of serines 170 and 178 reduced HBV replication at multiple stages, indicating that these residues also contribute to HBV replication. Thus, in addition to serines 157, 164, and 172, threonine 162 and serines 170 and 178 of HBV C protein are also phosphorylated in cells, and phosphorylation and dephosphorylation of these residues play multiple roles in modulation of HBV replication.</P><P><B>IMPORTANCE</B> Threonine 162, within the carboxyl-terminal end of the hepatitis B virus (HBV adw) core (C) protein, has long been ignored as a phosphoacceptor, even though it is highly conserved among mammalian hepadnaviruses and in the overlapping consensus RxxS/T, RRxS/T, and TP motifs. Here we show, for the first time, that in addition to the well-known phosphoacceptor serines 157, 164, and 172 in SPRRR motifs, threonine 162 and serines 170 and 178 in the RRRS/T motif are phosphorylated in cells. We also show that, like serines 157, 164, and 172, phosphorylated and dephosphorylated threonine 162 and serines 170 and 178 contribute to multiple steps of HBV replication, including pgRNA encapsidation, minus-strand and plus-strand DNA synthesis, and relaxed-circular DNA synthesis. Of these residues, threonine 162 is the most important. Furthermore, we show that phosphorylation of C protein is required for efficient completion of HBV replication.</P>

나노 오일을 이용한 압축기 습동부 재질의 윤활 특성 향상에 관한 연구

김성춘(Sungchoon Kim),김경민(Kyongmin Kim),황유진(Yujin Hwang),박영도(Youngdo Park),이재근(Jaekeun Lee) 대한설비공학회 2009 설비공학 논문집 Vol.21 No.10

Performance of refrigerant oil at the thrust-bearing and at the journal-bearing of a scroll compressor is a significant factor. This paper presents the friction and anti-wear characteristics of nano oil with a mixture of a refrigerant oil and carbon nano particles. The characteristics of friction and anti-wear using nano-oil is evaluated using the disk on disk tester for measuring friction surface temperature and the coefficient of friction. The average friction coefficient of nano-oil was reduced by 60% compared to raw oil under 600 N and 1,000 rpm. It is believed that the interaction of nano particles between surfaces can be improved the lubrication in the friction surfaces. Worn surfaces of frictional specimen were also investigated by the optical and atomic force microscopy. Conclusively, it is expected that wear and friction coefficient of compressor can be reduced by alignment applying nano-oil as refrigerant oil.

A animal Models of chemical induced esophageal stricture

Bo-Hwan Jin,Jae Chul Hwang,Kee Myung Lee,Kyongmin Kim,Jin Hong Kim 한국실험동물학회 2010 한국실험동물학회 학술발표대회 논문집 Vol.2010 No.8

Ribosome Display를 이용한 항체선별 방법의 확립

이명신,권명희,김경민,박선,신호준,김형일,Lee, Myung-Shin,Kwon, Myung-Hee,Hwang Kim, Kyongmin,Park, Sun,Shin, Ho-Joon,Kim, Hyung-Il 대한면역학회 2003 Immune Network Vol.3 No.3

Background: Phage display is the most widely used technique among display methods to produce monoclonal antibody fragment with a specific binding activity. Having a large library for efficient antibody display/selection is quite laborious process to have more than $10^9$ members of transformants. To overcome these limitations, several in vitro selection approaches have been reported. Ribosome display that links phenotypes, proteins, directly to genotype, mRNA, is one of the in vitro display methods. Ribosome display can reach the size of scFv library up to $10^{14}$ molecules and it can be further diversified during PCR steps. To select the high affinity scFv from one pot library, we established ribosome display technique by modifying the previously reported eukaryotic translation system. Methods: To establish the antibody selection system by ribosome display, we used 3D8, anti-DNA antibody. A 3D8 scFv was synthesized in vitro by an in vitro transcription-translation system. The translated 3D8 scFv and the encoding 3D8 mRNA are connected to the ribosome. These scFv-ribosome-mRNA complexes were selected by binding to their specific antigens. The eluted mRNAs from the complexes are reverse transcribed and re-amplified by PCR. To apply this system, antibody library from immunized mouse with terminal protein (TP)-peptide of hepatitis B virus DNA polymerase TP domain was also used. This TP-peptide encompasses the 57~80 amino acid residues of TP. These mRNA/ribosome/scFv complexes by our system were panned three times against TP-peptide. The enrichment of antibody from library was determined by radioimmunoassay. Results: We specifically selected 3D8, anti-DNA antibody, against ssDNA as a model system. The selected 3D8 RNAs sequences from translation complexes were recovered by RT-PCR. By applying this model system, we enriched TP-peptide-specific scFv pools through three cycles of panning from immunized library. Conclusion: We show that our translating ribosome complexes are well maintained and we can enrich the TP-specific scFv pools. This system can be applied to select specific antibody from an antibody library.

The Putative Transcriptional Activator MSN1 Promotes Chromium Accumulation in Saccharomyces cerevisiae

황성빈,장광석,Jong Im Won,이미란,Chang Eun Lee,Kyongmin Hwang Kim,박귀영,김성기,June Seung Lee 한국분자세포생물학회 2003 Molecules and cells Vol.16 No.3

Yeast is a good system for studying molecular mechanisms of metal tolerance. Using a mini-Tn mutagenized yeast pool, we isolated a chromate-tolerant mutant, CrT9, that displayed metal-specific tolerance since it was only tolerant to Cr(VI), not to Cr(III), Cd, As, or Fe. The Cr-tolerance of CrT9 appeared to be due to reduced Cr accumulation as it accumulated only 56% as much as WT (Y800). Using IPCR (inverse PCR), we found that the mini-Tn had been inserted at nt 741 of the transcriptional activator, MSN1. MSN1 is a multifunctional protein involved in invertase activity, iron uptake, starch degradation, pseudohyphal growth, and osmotic gene expression. We found that there was only one mini-Tn insertion in CrT9 since MSN1 and mini-Tn probes hybridized to the same DNA fragment, and the MSN1 probe detected an enlarged MSN1 mRNA. When we over-expressed MSN1 in CrT9 and WT, both accumulated larger amounts of Cr. We conclude that Cr accumulation in S. cerevisiae is promoted by the transcriptional activator MSN1.