• BMB Reports
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• v.29 no.1
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• pp.88-91
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• 1996

The anaerobically expressed gene aeg-46.5, which had been identified by the operon fusion technique with a hybrid bacteriophage of ${\lambda}$ and Mu, ${\lambda}$placMu53, was studied for its expression pattern and growth. The expression of aeg-46.5 was studied in the wild-type cell and mutant cells that have mutation (s) in the control gene of anaerobic respiration (fnr) and nitrate response (narL and narP). The ${\beta}$-galactosidase reporter gene showed maximum expression in narL host after two hours of aerobic to anaerobic switch in M9-Glc-nitrate medium. Both 40 mM and 100 mM concentrations of nitrate ion in the medium had little effect on expression level. We propose that aeg-46.5 is subject to multiple regulations of anaerobic activation by Fnr, nitrate activation by NarP and repression mediated by NarL.

• Journal of Microbiology and Biotechnology
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• v.9 no.4
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• pp.436-442
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• 1999

The aeg-46.5 operon of Escherichia coli is induced by nitrate and anaerobic conditions. Positive regulators Fnr and NarP, and a negative regulator NarL control the expression of the aeg-46.5. It has two symmetry regions [6], one of which is located between +37 and +56 bp from the 5'end of the anaerobic transcription initiation site. In this study, mutagenized symmetry regions were transferred from plasmid to chromosome by homologous recombination to evaluate the mutation as a single copy in the fnr, narL, narP, and narL-narP double mutant background. The expressions of the aeg-46.5 operon with these mutations indicated that the control was not through the possible stem-loop structure. Whether there is a protein that mediates this control remains to be seen. The results from the narL-narP double mutant indicated that the anaerobic Fill induction was independent of NarL repression.

• BMB Reports
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• v.29 no.1
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• pp.92-97
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• 1996

The age-46.5 gene of Escherichia coli is induced by nitrate ion and regulated by Fnr, NarL, and NarP during anaerobic growth. aeg-46.5::lacZ fusion gene shows its maximum expression in narL host after two hours of aerobic to anaerobic switch in M9-Glc-nitrate medium. Fnr and NarP act as positive regulators, and NarL acts as a negative regulator. The control region of the aeg-46.5 was identified and the binding sites of regulator proteins have been predicted (Reznikoff and Choe (1993)). It has two symmetry regions. One is located at -52~-37 bp from the anaerobic mRNA 5'-end, which is the binding site of NarL and NarP. The other is located at +37~+56 bp from the 5'-end of mRNA. In this study, the downstream symmetry region from the mRNA 5'-end was investigated by site-directed mutagenesis. The destruction of the symmetry region increases the expression level of aeg-46.5. We propose that the symmetry region interferes with the expression of aeg-46.5 possibly by forming a stem-and-loop structure.

• Korean Journal of Community Nutrition
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• v.20 no.6
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• pp.423-432
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• 2015

Objectives: In Korea, the percentage of elderly is increasing at an unprecedented rate, and is expected to account for 40% of the population by 2060. This massive demographic change stresses the importance of research on aging as it is necessary to improve the quality of life (QoL) of this population. This study aimed to examine the health-related quality of life (HRQoL) of the rural elderly and to clarify its association with the nutrient adequacy ratio (NAR). Methods: A cross-sectional study was performed in S-gun, Chonbuk, a critical agricultural area. The elderly people without abnormal physical functioning composed our study population and the data were collected by personal visits to 336 elderly people aged over 65 years (110 males and 226 females). Subjects were interviewed with questionnaires pertaining to general characteristics and EuroQol (EQ-5D). Nutrient intakes were assessed two days by 24-hours recall method. Subjects were defined as high QOL group if EQ-5D index with Nam's model was above the median. Results: Generally, EQ-5D index was lower in women than in man, and lower in older subjects than in younger subjects. The percentages of people below the median were 42% (low QoL group) and 58% (high QoL group) were found to be the above the median. The high QoL group had higher NAR, especially for vitamin C, vitamin B1, vitamin B2 and folate. All dimensions in the EQ-5D were affected by NAR of some nutrients and especially anxiety/depression dimension was significantly correlated with NAR of 5 nutrients (protein, calcium, iron, vitamin C and vitamin B1) and EQ-5D scores. Conclusions: HRQol was significantly reduced in elderly with increasing age and this was more pronounced in women than in man. The NAR of some nutrients were associated with the EQ-5D index, especially anxiety/depression dimension, among rural elderly.

• Journal of the Korean Society for Railway
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• v.10 no.6
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• pp.758-765
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• 2007

In this paper, we propose an efficient seamless handoff scheme to minimize packet loss and unnecessary packets on the Internet using the peculiar mobility characteristics of public vehicles such as trains. MR (Mobile Router) in a train visits each AR (Access Router) in the fixed order. As the MR detects reachability to the NAR (Next Access Router) on the new link, the PAR (Previous Access Router) can directly deliver packets from MR's HA (Home Agent) to the NAR according to the HML (Handoff Mobile router List). Then. the NAR buffers them until the MR finishes L3 (Layer 3) handoff procedure with the NAR. Therefore, our scheme can support a seamless handoff without the packet loss and unnecessary packets on the Internet. The result of our performance evaluation has shown that the proposed scheme could provide excellent performance, compared with the NEMO basic support protocol and the Bi-casting protocol.

• Macromolecular Research
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• v.16 no.5
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• pp.441-445
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• 2008

A series of aluminum complexes supported by $\beta$-ketoamino, ligand-bearing, 3-position substituents $LAlEt_2$ ($L=CH_3C(O)C(Cl)=C(CH_3)NAr\;(L_1)$, $L=CH_3C(O)C(H)=C(CH_3)NAr\;(L_2)$, $L=CH_3C(O)C(Ph)=C(CH_3)NAr\;(L_3)$, and $L=CH_3C(O)C(Me)=C(CH_3)NAr\;(L_4)$, $Ar=2,6-^iPr_2C6H_3$) were synthesized in situ and employed in the ring-opening polymerization (ROP) of $\varepsilon$-caprolactone ($\varepsilon$-CL) and cyclohexene oxide (CHO). The 3-position substituents on the $\beta$-ketoamino ligand backbone of the aluminum complexes influenced the catalyst activity remarkably for both ROP of $\varepsilon$-CL and CHO. Aluminum $\beta$-ketoamino complexes displayed different catalytic behavior in ROP of $\varepsilon$-CL and CHO. The order of the catalytic activity of $LAlEt_2$ was $L_1AlEt_2$>$L_2AlEt_2$>$L_3AlEt_2$>$L_4AlEt_2$ for ROP of $\varepsilon$-CL, being opposite to the electron-donating ability of the 3-position substituents on the $\beta$-ketoamino ligand, while the order of the catalytic activity for ROP of CHO was $L_1AlEt_2$>$L_3AlEt_2$>$L_4AlEt_2$>$L_2AlEt_2$. The effects of reaction temperature and time on the ROP were also investigated for both $\varepsilon$-CL and CHO.

• The Korean Journal of Ecology
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• v.18 no.2
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• pp.255-263
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• 1995

Two poplar clones, I-214 (Populus euramericana) and Peace (P. Koreana × P. trichocarpa), were grown for 21 days in growth chambers at different CO₂concentrations (350, 700 and 2,000 μL·L-1). I-214 has stomata responding to environmental conditions in normal ways and Peace has unresponsive stomata to environmental factors including light, ABA, water stress and CO₂. In both plants, elevated CO₂ stmulated the growth of plant parts, especially leaf dry weight. And a CO₂ enrichment of 700 μL·L-1 CO₂ caused increment of net assimilation rate (NAR). The growth responses of these plants to CO₂ enrichment were different especially at high CO₂ condition (2,000 μL·L-1 CO₂). The total dry weight in Peace increased up to 2,000 μL·L-1 CO₂ but not in I-214. A CO₂ enrichment of 2,000 2,000 μL·L-1 CO₂ had little effect on NAR of I-214 but enhanced NAR of Peace. Although it is uncertain whether the different responses to CO₂ enrichment between I-214 and Peace resulted from the different properties of stomatal responses to long-term CO₂ treatment, the decrease in NAR is probably due in part to CO₂-induced stomatal closure in I-214 but not in Peace.

• Bulletin of the Korean Chemical Society
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• v.22 no.8
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• pp.903-908
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• 2001

The gene aeg-46.5, which is expressed under anaerobic condition, has putative triple -10 regions and four transcription start sites. The mRNA transcription level and its start point change depending on the aerobic/anaerobic growth condition. RNA polymerase and its regulatory proteins must choose which of three -10 region to use. The putative triple 10 region was mutated to make only one of them function with consensus -10 region sequence (TATAAT) and the other two as non-functional region. The results show that the second and third -10 regions are used for the aerobic/anaerobic expression. The third -10 region is responsible for the high aerobic to anaerobic switch ratio. This suggests that only the last two of the putative triple -10 region have functions on aeg-46.5 gene expression switch control. The phenotype of the mutated promoter was tested in the wild type cell and narL - cell. The results indicate that the control by NarL is independent from the selection of -10 region. The expression patterns on multi-copy plasmids and on single-copy chromosome were compared. These results show that the aerobic/anaerobic switch control of aeg-46.5 is through the choice of -10 region. The mechanism of choosing different -10 region remains to be seen.

• The Korean Journal of Pain
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• v.35 no.3
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• pp.291-302
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• 2022

Background: Spinal cord injury (SCI) is one of the most debilitating disorders throughout the world, causing persistent sensory-motor dysfunction, with no effective treatment. Oxidative stress and inflammatory responses play key roles in the secondary phase of SCI. Naringenin (NAR) is a natural flavonoid with known anti-inflammatory and antioxidative properties. This study aims at evaluating the effects of intrathecal NAR administration on sensory-motor disability after SCI. Methods: Animals underwent a severe compression injury using an aneurysm clip. About 30 minutes after surgery, NAR was injected intrathecally at the doses of 5, 10, and 15 mM in 20 µL volumes. For the assessment of neuropathic pain and locomotor function, acetone drop, hot plate, inclined plane, and Basso, Beattie, Bresnahan tests were carried out weekly till day 28 post-SCI. Effects of NAR on matrix metalloproteinase (MMP)-2 and MMP-9 activity was appraised by gelatin zymography. Also, histopathological analyses and serum levels of glutathione (GSH), catalase and nitrite were measured in different groups. Results: NAR reduced neuropathic pain, improved locomotor function, and also attenuated SCI-induced weight loss weekly till day 28 post-SCI. Zymography analysis showed that NAR suppressed MMP-9 activity, whereas it increased that of MMP-2, indicating its anti-neuroinflammatory effects. Also, intrathecal NAR modified oxidative stress related markers GSH, catalase, and nitrite levels. Besides, the neuroprotective effect of NAR was corroborated through increased survival of sensory and motor neurons after SCI. Conclusions: These results suggest intrathecal NAR as a promising candidate for medical therapeutics for SCI-induced sensory and motor dysfunction.

• Korean Chemical Engineering Research
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• v.44 no.6
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• pp.659-668
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• 2006

The optimization of supercritical water oxidation (SCWO) process for decomposing nitromethane was studied by means of a design of experiments. The optimum operating region for the SCWO process to minimize COD and T-N of treated water was obtained in a lab scale unit. The authors had compared the results from a SCWO pilot plant with those from a lab scale system to explore the problems of scale-up of SCWO process. The COD and T-N in treated waters were selected as key process output variables (KPOV) for optimization, and the reaction temperature (Temp) and the mole ratio of nitromethane to ammonium hydroxide (NAR) were selected as key process input variables (KPIV) through the preliminary tests. The central composite design as a statistical design of experiments was applied to the optimization, and the experimental results were analyzed by means of the response surface method. From the main effects analysis, it was declared that COD of treated water steeply decreased with increasing Temp but slightly decreased with an increase in NAR, and T-N decreased with increasing both Temp and NAR. At lower Temp as $420{\sim}430^{\circ}C$, the T-N steeply decreased with an increase in NAR, however its variation was negligible at higher Temp above $450^{\circ}C$. The regression equations for COD and T-N were obtained as quadratic models with coded Temp and NAR, and they were confirmed with coefficient of determination ($r^2$) and normality of standardized residuals. The optimum operating region was defined as Temp $450-460^{\circ}C$ and NAR 1.03-1.08 by the intersection area of COD < 2 mg/L and T-N < 40 mg/L with regression equations and considering corrosion prevention. To confirm the optimization results and investigate the scale-up problems of SCWO process, the nitromethane was decomposed in a pilot plant. The experimental results from a SCWO pilot plant were compared with regression equations of COD and T-N, respectively. The results of COD and T-N from a pilot plant could be predicted well with regression equations which were derived in a lab scale SCWO system, although the errors of pilot plant data were larger than lab ones. The predictabilities were confirmed by the parity plots and the normality analyses of standardized residuals.