• Journal of Microbiology and Biotechnology
• /
• v.25 no.4
• /
• pp.492-495
• /
• 2015

This study provides evidence that RecG regulates the expression of the OxyR-independent gene mexA in Pseudomonas aeruginosa PAO1. A reduction in mexA expression was observed in the absence of RecG, but not OxyR, by northern blot and quantitative real-time PCR analyses. The canonical palindromic RecG binding sequence was present upstream of the mexA promoter, and bound purified RecG and single strand-binding protein. These data reveal a novel mechanism of OxyR-independent gene transcription by RecG.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.28 no.8
• /
• pp.316-324
• /
• 2016

This study investigated a compact regenerative evaporative cooler (REC). To achieve practical applications of an REC, it is very important to consider the compactness as well as the cooling performance. Therefore, a prototype of the REC was designed and fabricated to improve the compactness by reducing the length through the insertion of fins in both the dry and wet channels. The REC prototype was tested in terms of performance evaluation under various operating conditions. An analytical model was also developed to analyze the effects of the axial conduction through the solid body of the REC, the wetness of the surface in the wet channel, and the thermal capacity of the evaporation water flow. The model was validated by comparing the results of a simulation with experimental data. The numerical simulation was based on the model to analyze the performance of the REC and to suggest methods to improve the cooling performance of the REC. Finally, the performance of the present REC was compared to that obtained in previous experimental studies. The results showed that the REC prototype in the present study is the most compact and achieves the highest cooling performance.

• Journal of Life Science
• /
• v.28 no.5
• /
• pp.587-596
• /
• 2018

This study aims to observe changes in heart-rate variability (HRV) indices induced by e-cigarette and conventional-cigarette smoking and to compare the differences in acute cardiac autonomic regulation. All participants (n=41) were exposed to both e-cigarette smoke (ES) and conventional cigarette smoke (CS) in a randomized crossover trial. HRV analysis was performed during each smoking session based on a recorded r-r interval 10 minutes before smoking and at specified recovery periods (REC1, 0-5 min; REC2, 5-10 min; REC3, 10-15 min; REC4, 15-20 min; REC5, 20-25 min; and REC6, 25-30 min). ES led to a significantly increased cardiac sympathetic index (LF/HF ratio) compared with the baseline, and it shifted the sympathovagal balance toward sympathetic predominance, including reduction in the complexity of the interbeat interval (SampEn). In REC1 after ES, only decreases of parasympathetic indices such as rMSSD, pNN50, HF, and SD1 were indicated. CS sessions produced not only an increased LF/HF ratio during smoking and recovery periods (REC1 and REC4) but also enhanced sympathetic predominance on autonomic balance during smoking and recovery periods (REC1, REC2, and REC4). In the CS trials, parasympathetic indices of time and non-linear analysis (rMSSD, pNN50, and SD1) were decreased during smoking and in REC1 to REC5. SampEn was also reduced during smoking and REC1 to REC4. Acute sympathoexcitatory effects induced by e-cigarette use produced statistically significant results. Parasympathetic withdrawal after smoking suggests that e-cigarettes may cause increased cardiovascular risk.

• Journal of Sericultural and Entomological Science
• /
• v.38 no.1
• /
• pp.42-47
• /
• 1996

To investigate the host range determining factors of nuclear polyhedrois virus (NPV), Autographa california NPV and Bombyx mori NPV were coinfected into the two different cell lines, BmN-4 and Sf-9. The recombinant baculoviruses, RecS-A6 and RecB-727 which have an expanded host range, were isolated from Sf-9 and BmN-4 cell lines, respectively. The molecular biological characteristics of the recombinant baculoviruses were investigated. The pathogenicity of RecB-727 was similar to that of wild type BmNPV, while the pathogenicity of RecS-A6 was relatively lower than that of wild type BmNPV. The restriction enzyme digestion patterns of parental viruses and recombinant viruses showed that the recombinant virus has an expanded host range by genetic recombination. Southern blot analysis revealed that the p10 gene of RecB-727 was derived from AcNPV genomic DNA, while RecS-A6 has p10 gene of BmNPV in a viral genome. To investigate the host range expansion mechanism of recombinant baculovirus, HindIII-SacI 0.6 kb DNA fragments of RecS-A6 and RecB-727 were cloned and sequenced. The results showed that of wild type BmNPV helicase gene, suggesting that the expanded host range of recombinant baculoviruses was due to the insertion of BmNPV helicase gene into AcNPV viral genome.

• Journal of the Korea Convergence Society
• /
• v.12 no.6
• /
• pp.139-150
• /
• 2021

Currently, the RPS(Renewable Portfolio Standard) is the policy which supplies new and renewable energy. Power generation companies with large capacity should produce renewable energy or secure through the purchase of REC (Renewable Energy Certificates) as mandatory. The government has revised the REC weight several times, which weights each energy source by evaluating the economic and social value of renewable energy sources, and revised the mandatory supply ratio to gradually increase. This study helps to find the impact of policies on related industries. In this study, time-series analysis and regression analysis on the capacity of PV(Photovoltaics) facilities as a dependent variable were performed to analyze the effect of the revision of the REC weight for photovoltaic power generation and the amount of mandatory supply for renewable energy. As a result, it was statistically assessed that the revision of the REC weight and the increase in the mandatory supply has a significant effect on the increase in the amount of PV facilities.

• BMB Reports
• /
• v.32 no.5
• /
• pp.436-439
• /
• 1999

Shigella sonnei is an important cause of human enteric infections. S. sonnei KNIH104S was previously reported to be isolated from Korean shigellosis patients. We cloned a 2.8-kb KpnI fragment containing the recA gene encoding a recombinase from the chromosomal DNA of S. sonnei KNIH104S. This recombinant plasmid was named pRAK28. E. coli HB101, a recA mutant, cannot grow on Luria-Bertani medium in the presence of the alkylating agent methylmethane sulfonate, however, E. coli HB101 harboring pRAK28 was found to grow on this medium. As far as we know, we are the first to sequence the recA gene from S. sonnei. This gene is composed of 1062 base pairs with an ATG initiation codon and a TAA termination codon. Nucleotide sequence comparison of the S. sonnei recA gene exhibited 99.7% and 99.5% identity with those of S. flexneri and E. coli, respectively.

• Korean Institute of Interior Design Journal
• /
• v.19 no.5
• /
• pp.226-233
• /
• 2010

This study is to analyze and determine the emotional design on domestic rec-education space, in order to propose a way to design children rec-education space. A study is on reviewing needs and verify categories of emotional design through interior design of rec-education space, A study procedure will begin with theoretical proofing of children rec-education and move on to needs of emotional design in interior design and types of analysis for it. With this procedure, we will project adequate way for emotional characteristics in rec-education space and will analyze types of it from interior design of rec-education space in nine different domestic brands. With this background, we like to present methods and reveal characteristics of it. The conclusion on this study is described as followed. First, children rec-education space has positively carried types of emotional characteristics: experimental, continuity, and symbolism. Second, Some precondition; application through types of pattern, experimentation on light in space, continuity on linear interior space composition, symbolism in abstract implementation, and physical control over designed subject, has low effectiveness on creating emotional space by applying such scale matters. Third, the actual interior design subject matters and supporting facilities' textural accommodation is inadequately built for their majority, children, whether it is direct or indirect for contact. Forth, Even though to carry emotional space needs some kinds of story telling and prerequisite sequential space composition, there are lack of applicable space compositions. For this reason, it needs on going study in emotional space for children rec-education space. Last, there are needs for researching a depth understanding and presenting different characteristics of emotional interior design by brands.

• Journal of Sericultural and Entomological Science
• /
• v.38 no.1
• /
• pp.36-41
• /
• 1996

Recombinant baculoviruses having expanded host range were selected by coinfection of Autographa california NPV and Bombyx mori NPV into Sf-9 and BmN-4 insect cell lines. In order to determine the polyhedra morhplogy of RecS-A6, one of a recombinant baculovirus, polyhedra of RecS-A6 produced in insect cells were observed by phase contrast microscope and scanning electron microscope. The results revealed that the recombinant baculovirus had a various polyhedra morphology which was different from its parental viruses, suggesting that the various morhpology of recombinant baculovirus with an expanded host range was due to the genetic recombination of viral genome. To analyze the genomic recombinantion of the recombinant baculoviruses, genomic DNAs of two parent viruses and RecS-A6 were digested with restriction endonuclease and subjected to agarose gel electrophoresis. Southern blot analysis revealed that RecS-A6 has two polyhedrin gene of AcNPV and BmNPV in a viral genome. Polyhedral protein of recombinant baculovirus was analysed by SDS-PAGE. The result showed that molecular weight of polyhedral protein of RecS-A6 containing two polyhedrin gene of AcNPV and BmNPV was as the 31 kDa band of AcNPV and 30 kDa band of BmNPV.

• The Korean Journal of Zoology
• /
• v.38 no.4
• /
• pp.565-569
• /
• 1995

We have previoosly demonstrated that the RecA-like protein of Schizosaccharomyces pombe (S. pombe) is immunologically related to Escherichia coil (E. coil) RecA protein and that the cellular level of the protein is significantly increased by inhibitors of nucleotide pool-forming enzymes such as hydroxyurea (HU) and methotrexate (MTX) (lee and Park, 1994; lee et al., 1994). In this study, we report that the ribonudeotide redudase activity of S. pombe is inhibited by E. coil RecA antibody, as determined by thin layer chromatography using [5-$^3$H]CDP as a substrate. The relative activity of ribonucleotide reductase was dramatically inhibited by 100 mM of flu (26.4% reduction) in in vitro assay, compared to that of non-treated control. The ribonucleotide reductase activity was also inhibited by immunoprecipitation with E. coil RecA antibody (43.3% reduction). These results indicate that the strudure of S. pombe ribonucleotide reductase is in part similar to that of E. coil RecA protein.

• Journal of Microbiology and Biotechnology
• /
• v.13 no.1
• /
• pp.99-103
• /
• 2003

An Escherichia coli strain containing the recA promoter that fused to the luxCDABE operon originating from Photorhabdus luminescens was shown to respond sensitively to genotoxic stresses. Two different recombinant bacteria, one (DPDI 657) harboring a plasmid with the recA promoter that fused to the luxCDABE operon, and the other (DPD1710) containing a chromosomally-integrated recA promoter that fused with luxCDABE, were compared and it was found that the sensitivity of 'the two strains was significantly different in terms of their bioluminescent level, response time, and the minimum detectable concentration of a chemical causing DNA damaging stress. DPDI 710, with a chromosomally-integrated single copy, generally led to lower basal luminescence levels, faster responses, increased response ratios, and an enhanced sensitivity to mutagens, when compared to DPD 1657 with a multi-copy plasmid.