• Journal of the Korea Society of Computer and Information
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• v.17 no.5
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• pp.41-48
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• 2012

A Vehicular Ad-hoc Network (VANET) is a vehicular specific type of a mobile ad-hoc network, to provide temporary communications among nearby vehicles. Mobile node of VANET consumes energy and resource with participating in the member of network. In a VANET, data replication and cooperative caching have been used as promising solutions to improve system performance. Existing cooperative caching scheme in a VANET mostly focuses on weak consistency is not always satisfactory. In this paper, we propose an efficient cache management scheme to maintain strong data consistency in a VANET. We make an adaptive scheduling scheme to broadcast Invalidation Report (IR) in order to reduce query delay and communication overhead to maintain strong data consistency. The simulation result shows that our proposed method has a strength in terms of query delay and communication overhead.

• Journal of KIISE:Computer Systems and Theory
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• v.36 no.5
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• pp.360-370
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• 2009

Using solar power in wireless sensor networks requires a different approach to energy optimization from networks with battery-based nodes. Solar energy is an inexhaustible supply which can potentially allow a system to run forever, but there are several issues to be considered such as the uncertainty of energy supply and the constraint of rechargeable battery capacity. In this paper, we present SolarSS: a reliable storage system for solar-powered sensor networks, which provides a set of functions, in separate layers, such as sensory data collection, replication to prevent failure-induced data loss, and storage balancing to prevent depletion-induced data loss. SolarSS adapts the level of layers activated dynamically depending on solar energy availability, and provides an efficient resource allocation and data distribution scheme to minimize data loss.

• Korean Journal of Veterinary Research
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• v.58 no.1
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• pp.9-16
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• 2018

A preliminary study into the protective mechanisms of adaptive immunity against porcine reproductive and respiratory syndrome virus (PRRSV) in piglets (n = 9) born to a gilt challenged intranasally with a type-2 PRRSV. Immune parameters (neutralizing antibodies, $CD3^+CD4^+$, $CD3^+CD8^+$, $CD3^+CD4^+CD8^+$ T-lymphocytes, and PRRSV-specific interferon $(IFN)-{\gamma}$ secreting T-lymphocytes) were compared with infection parameters (macro- and microscopic lung lesion, and PRRSV-infected porcine alveolar macrophages ($CD172{\alpha}^+PRRSV-N^+\;PAM$) as well as with plasma and lymphoid tissue viral loads. Percentages of three T-lymphocyte phenotypes in 14-days post-birth (dpb) peripheral blood mononuclear cell (PBMC) had significant negative correlations with percentages of $CD172{\alpha}^+PRRSV-N^+\;PAM$ (p < 0.05) as well as with macroscopic lung lesion (p < 0.01). Plasma and tissue viral loads had significant (p < 0.05) negative correlations with $CD3^+CD4^+CD8^+$ T-lymphocyte percentage in PBMC. Frequencies of $CD3^+CD8^+$ and $CD3^+CD4^+$ T-lymphocytes in 14-dpb PBMC had significant negative correlations with of lymph node (p = 0.04) and lung (p = 0.002) viral loads. $IFN-{\gamma}$-secreting T-lymphocytes frequency had a significant negative correlation with gross lung lesion severity (p = 0.002). However, neutralizing antibody titers had no significant negative correlation (p > 0.1) with infection parameters. The results indicate that T-lymphocytes contribute to controlling PRRSV replication in young piglets born after in-utero infection.

• Journal of Microbiology and Biotechnology
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• v.31 no.4
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• pp.510-519
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• 2021

The pathological impact of haze upon the phyllosphere microbiota awaits investigation. A moderate degree of haze environment and a clean control were selected in Chengdu, China. Artemisia argyi, a ubiquitously distributed and extensively applied Chinese herb, was also chosen for experiment. Total genome DNA was extracted from leaf samples, and for metagenome sequencing, an Illumina HiSeq 2500 platform was applied. The results showed that the gene numbers of phyllosphere microbiota derived from haze leaves were lower than those of the clean control. The phyllosphere microbiota derived from both haze and clean groups shared the same top ten phyla; the abundances of Proteobacteria, Actinomycetes and Anorthococcuso of the haze group were substantially increased, while Ascomycetes and Basidiomycetes decreased. At the genus level, the abundances of Nocardia, Paracoccus, Marmoricola and Knoelia from haze leaves were markedly increased, while the yeasts were statistically decreased. KEGG retrieval demonstrated that the functional genes were most annotated to metabolism. An interesting find of this work is that the phyllosphere microbiota responsible for the synthesis of primary and secondary metabolites in A. argyi were significantly increased under a haze environment. Relatively enriched genes annotated by eggNOG belong to replication, recombination and repair, and genes classified into the glycoside hydrolase and glycosyltransferase enzymes were significantly increased. In summary, we found that both structure and function of phyllosphere microbiota are globally impacted by haze, while primary and secondary metabolites responsible for haze tolerance were considerably increased. These results suggest an adaptive strategy of plants for tolerating and confronting haze damage.

• Journal of Life Science
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• v.30 no.1
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• pp.88-95
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• 2020

Using a random arbitrarily primed polymerase chain reaction, messenger RNA expression levels were assessed after exposure to 10% (v/v) toluene for 8 hr in solvent-tolerant Pseudomonas sp. BCNU 106. Among the 100 up-expressed products, 50 complementary DNA fragments were confirmed to express repeatedly; these were cloned and then sequenced. Blast analysis revealed that toluene stimulated an adaptive increase in the gene expression level in association with transcriptions such as LysR family of transcriptional regulators and RNA polymerase factor sigma-32. The expression of catalase and Mn2+/Fe2+ transporter genes functionally associated with inorganic ion transport and metabolism increased, and the increased expression of type IV pilus assembly PilZ and multi-sensor signal transduction histidine kinase genes, functionally categorized into signal transduction and mechanisms, was also demonstrated under toluene stress. The gene expression level of beta-hexosaminidase in association with carbohydrate transport and metabolism increased, and those of DNA polymerase III subunit epsilon, DNA-3-methyladenine glycosylase II, DEAD/DEAH box helicase domain-containing protein, and ABC transporter also increased after exposure to toluene in DNA replication, recombination, and repair, and even in defense mechanism. In particular, the RNAs corresponding to the ABC transporter, Mn2+/Fe2+ transporter, and the β-hexosaminidase gene were confirmed to be markedly induced in the presence of 10% toluene. Thus, defense mechanism, cellular ion homeostasis, and biofilm formation were shown as essential for toluene tolerance in Pseudomonas sp. BCNU 106.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.2
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• pp.423-430
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• 2013

Recently, the personal identification technologies using vein pattern of back of the hand, palm, and finger have been developed actively because it has the advantage that the vein blood vessel in the body is impossible to damage, make a replication and forge. However, it is difficult to extract clearly the vein region from captured vein images through common image prcessing based region segmentation method, because of the light scattering and non-uniform internal tissue by skin layer and inside layer skeleton, etc. Especially, it takes a long time for processing time and makes a discontinuity of blood vessel just in a image because it has non-uniform illumination due to use a locally different adaptive threshold for the binarization of acquired finger-vein image. To solve this problem, we propose illumination normalization based fast method for extracting the finger-vein region. The proposed method has advantages compared to the previous methods as follows. Firstly, for remove a non-uniform illumination of the captured vein image, we obtain a illumination component of the captured vein image by using a low-pass filter. Secondly, by extracting the finger-vein path using one time binarization of a single threshold selection, we were able to reduce the processing time. Through experimental results, we confirmed that the accuracy of extracting the finger-vein region was increased and the processing time was shortened than prior methods.

• Journal of Microbiology and Biotechnology
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• v.23 no.8
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• pp.1159-1166
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• 2013

Orientia tsutsugamushi, a gram-negative bacterium, causes severe acute febrile illness in humans. Despite this danger, the route of infection, infectivity, and protective mechanisms of the host's immune response to O. tsutsugamushi are unclear. Dendritic cells (DCs) are one of the most important cell types in bridging the innate and adaptive immune responses. In this study, we observed that O. tsutsugamushi infects and replicates in monocyte-derived DCs (MODCs). During infection and replication, the expressions of the cytokines IL-12 and TNF-${\alpha}$, as well as the co-stimulatory molecules CD80, CD83, CD86, and CD40, were increased in MODCs. When O. tsutsugamushi-treated MODCs were co-cultured with autologous $CD4^+$ T cells, they enhanced production of IFN-${\gamma}$, a major Th1 cytokine. Collectively, our results show that O. tsutsugamushi can replicate in MODCs and can simultaneously induce MODC maturation and increase proinflammatory cytokine levels in MODCs that subsequently activate $CD4^+$ T cells.

• Journal of Life Science
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• v.32 no.2
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• pp.94-100
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• 2022

Chronic infection by hepatitis B virus (HBV) greatly increases the risk for liver cirrhosis and hepatocellular carcinoma (HCC). The outcome of HBV infection is shaped by the complex interplay of the mode of transmission, host genetic factors, viral genotype, adaptive mutations, and environmental factors. The pregenomic RNA transcription of HBV for their replication is regulated by the core promoter activation. Core promoter mutations have been the reason for acute liver failure and are associated with HCC development. We obtained HBV genes from a patient in Myanmar who was infected with HBV and identified gene variations in the core promoter region. For measuring the relative transactivation activity of the core promoter, we prepared the core-promoter reporter construct. Among the gene variations of the core promoter, the mutations of C1731T and G1806A were associated with increase in the transactivation of the HBV core promoter. Through computer analysis for searching for a tentative transcription factor binding site, we showed that the mutations of C1713T and G1806A newly created C/EBPβ and XBP1-responsive elements of the core promoter, respectively. The ectopic expression of C/EBPβ largely increased the HBV core promoter containing the C1713T mutation and that of XBP1 activated the M95 promoter containing the G1806A mutation. Our efforts to treat and prevent HBV infections are hampered by the emergence of drug-resistant mutations and vaccine-escape mutations. Our results provide the biological properties and clinical significance of specific HBV core promoter mutations.