• Journal of Microbiology and Biotechnology
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• v.18 no.1
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• pp.43-47
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• 2008

The nickel and cobalt resistance of Cupriavidus metallidurans CH34 is mediated by the CnrCBA efflux pump encoded by the cnrYHXCBAT metal resistance determinant. The products of the three genes cnrYXH transcriptionally regulate expression of cnr. CnrY and CnrX are membrane-bound proteins, probably functioning as anti-sigma factors, whereas CnrH is a cnr-specific extracytoplasmic functions (ECF) sigma factor. The periplasmic domain of CnrX (residues 29-148) was cloned as a N-terminal His-tagged protein, expressed in Escherichia coli, and purified using affinity chromatography and gel filtration. The molecular mass was estimated to be about 13.6kDa by size exclusion chromatography, corresponding to a monomer. The tetragonal bipyramid crystals were obtained by mixing an equal volume of protein in 50mM Tris-HCl, pH 7.5, 1% glycerol, 100mM NaCl, 1mM DTT, and the reservoir solution of 15% w/v PEG 2000, 100mM lithium chloride at 277K in 2-4 days using hanging drop vapor diffusion. The protein concentration was 24mg/ml. The crystal that diffracted to $2.42{\AA}$ resolution belongs to space group $P4_1\;or\;P4_3$ with unit cell parameters of $a=b=32.14{\AA},\;c=195.31{\AA},\;{\alpha}={\beta}={\gamma}=90^{\circ}$, with one molecule of CnrX in the asymmetric unit.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.255-259
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• 2015

Recent narrow-band Ca photometry discovered two distinct red giant branch (RGB) populations in some massive globular clusters (GCs) including M22, NGC 1851, and NGC 288. In order to investigate the differences in light/heavy elements abundances between the two subpopulations, we have performed low-resolution spectroscopy for stars on the two RGBs in these GCs. We find a significant difference (more than $4{\sigma}$) in calcium abundance from the spectroscopic HK' index for both M22 and NGC 1851. We also find a more than $8{\sigma}$ difference in CN band strength between the Ca-strong and Ca-weak subpopulations. For NGC 288, however, we detect the presence of a large difference only in the CN strength. The calcium abundances of the two subpopulations in this GC are identical within errors. We also find interesting differences in CN-CH relations among these GCs. While CN and CH indices are correlated in M22, they show an anti-correlation in NGC 288. However, NGC 1851 shows no difference in CH between two groups of stars having different CN strengths. The CN bimodality in these GCs could be explained by pollution from intermediate-mass asymptotic giant branch stars and/or fast-rotating massive stars. For the presence or absence of calcium bimodality and the differences in CN-CH relations, we suggest these would be best explained by how strongly type II supernovae enrichment has contributed to the chemical evolutions of these GCs.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.8
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• pp.1103-1109
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• 2002

This study investigated the effect of 2-bromo-$\alpha$-ergocryptine (anti prolactin agent) on plasma levels of prolactin, oestradiol-17$\beta$ and progesterone in domestic hen during the active period of lay. Fifty healthy female White Leghorn birds were administered with anti prolactin agent (2-bromo-$\alpha$-ergocryptine, Sigma-USA., methane sulphonate salt, $C_{32}H_{40}BrN_5O_5.CH_4SO_3$) subcutaneously @100$\mu$g/kg body weight at weekly intervals from 17th to 36th week of age. Another group of fifty birds as controls were given placebo in place of bromocriptine. The level of prolactin remained lower in treated birds than in the control birds from 19 to 36 weeks of age. Level of prolactin even in the control group was found to decrease during the peak production period. Oestradiol-$17{\beta}$ and progesterone concentration in treated birds were significantly (p<0.01) higher than the controls during the treatment. Egg production, is positively correlated with oestradiol-$17{\beta}$ (r=0.02; r=0.67) and progesterone (r=0.49; r=0.90) in control and treated groups respectively where as prolactin level is positively correlated with egg production in the control birds (r=0.07). Prolactin levels were negatively correlated with egg production (r=-0.55) in treated birds; and oestradiol-$17{\beta}$ (r =-0.71; r=-0.53) and progesterone (r=-0.22; r=-0.27) respectively in control and treated groups. The total number of pause days during the treatment period decreased significantly (p<0.01) in the treated group compared to the control group. The reduction in pause days in treated group resulted in 1.76% increase in egg production over that in control group. The increase in egg laying days and the total egg production were found to be significant (p<0.01). These results indicate that a lower level of prolactin in circulatory blood enhances egg production in the domestic hen.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.24 no.1
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• pp.36-44
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• 2011

Objective : Propolis (PP) has been used in oriental medicine. PP has various biological activities. However, its immunoregulatory and anti-inflammatory activities have not been well studied. In this study, I investigated these activities of PP by using ovalbumin-induced allergic asthma in mice. Methods : To examine the effect of PP on allergic asthma, mice were sensitized with $100{\mu}g$ of OVA and 1mg of aluminum potasssium sulfate (Alum; Sigma) intraperitoneally on day 0 and 7. On day 14, mice were challenged on consecutive 3 days with 5% OVA and AHR was assessed 24 hours after the last challenge. To examine severity of AHR, I examined the population of eosinophiles and T cells in spleen and lung and cytokine production in T cells. Futhermore, I examined histological changes during the OVA-induced allergic asthma. Results and Conclusion : PP reduced the population of eosinophil and CD4+ T cells on the OVA-induced AHR mice model. PP also inhibited IL-4 production but increased INF-g production in T cells. These results suggest that PP may be beneficial material for allergic asthma.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.1
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• pp.491-494
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• 2006

Kalman filtering (KF) is hard to be applied to the SINS (Strap-down Inertial Navigation System)/RDSS (Radio Determination Satellite Service) integrated navigation system directly because the time delay of RDSS positioning in active mode is random. BP (Back-Propagation) Neuron computing as a powerful technology of Artificial Neural Network (ANN), is appropriate to solve nonlinear problems such as the random time delay of RDSS without prior knowledge about the mathematical process involved. The new algorithm betakes a BP neural network (BPNN) and velocity feedback to aid KF in order to overcome the time delay of RDSS positioning. Once the BP neural network was trained and converged, the new approach will work well for SINS/RDSS integrated navigation. Dynamic vehicle experiments were performed to evaluate the performance of the system. The experiment results demonstrate that the horizontal positioning accuracy of the new approach is 40.62 m (1 ${\sigma}$), which is better than velocity-feedback-based KF. The experimental results also show that the horizontal positioning error of the navigation system is almost linear to the positioning interval of RDSS within 5 minutes. The approach and its anti-jamming analysis will be helpful to the applications of SINS/RDSS integrated systems.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.28 no.4
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• pp.74-91
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• 2015

Background and Objective : Asthma is a chronic inflammatory disease at the mucosa and is associated with excess production of Th2 cytokine and eosinophil accumulation in lung.Gamchomahwang-tangextract(GME) is one of the well known prescription used in oriental medicine for treating asthma. This study was designed to compare the anti-asthmatic effect of GME according to the ratio of 2 compounds.Methods : To examine the effects of GME on asthma, mice were sensitized with 100 ㎍ of OVA and 1 ㎎ of aluminum potassium sulfate(Alum; Sigma) intraperitoneally on day 1 and 15. From day 22, mice were challenged on 3 consecutive days with 5% OVA. The anti-asthmatic effects of GME were evaluated by enhanced pause(Penh), bronchoalveolar lavage fluids (BALF), inflammatory cytokine production and genes expression, serum IgE production. and histological change in lung tissue. GMEⅠ consists of ES and GU in the proportion 2:1(300 ㎎/㎏ group), GMEⅡ consist of ES and GU in the proprtion 4:1(300 ㎎/㎏ group).Results : GMEⅠ,Ⅱ generally inhibited lung inflammation, inflammatory cells infiltration and cytokine production and gene expression such as IL-4, IL-5 and IL-13 in BALF and serum IgE level. GMEⅡ significantly reduced the cytokine production and gene expression such as IL-4, IL-5 and IL-13 in BALF and GMEⅠ decreased cytokine production of IL-4, IL-13 in BALF and gene expression of IL-4, IL-5 in Lung. GMEⅡ potently inhibited the development of Penh and also reduced the number of eosinophil during OVA-induced AHR(airway hyper-reactivity). Overall the results show that GMEⅡ has more effect on inhibiting production, gene expression of cytokine, serum IgE level and development of Penh than GMEⅠ. Consequently, GMEⅡ might be more effective than GMEⅠ at inhibiting allergic asthma on the OVA-induced mice model.Conclusion : These results indicate that GME has a deep inhibitory effects on airway inflammation and hyperresponsiveness in mice model of asthma and that suppression of IL-4, IL-5, IL-13 expression and decrease of IL-4, IL-5, IL-13 production in BALF might contribute this effect. Hence, the results indicate that GME might be useful herbal medicine of allergic asthma. As a result, GMEⅡ mght be superior to GMEⅠ in the aspect of anti-asthmatic effect on the OVA-induced mice model.

• Bulletin of the Korean Chemical Society
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• v.24 no.5
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• pp.583-592
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• 2003

The gas phase identity nucleophilic substitution reactions of halide anions (X = F, Cl, Br) with cyclopentadienyl halides (1) are investigated at the B3LYP/6-311+G**, MP2/6-311+G** and G2(+)MP2 levels involving five reaction pathways: σ-attack $S_N2$, β-$S_N$2'-syn, β-$S_N$2'-anti, γ-$S_N$2'-syn and γ-$S_N$2'-anti paths. In addition, the halide exchange reactions at the saturated analogue, cyclopentyl halides (2), and the monohapto circumambulatory halide rearrangements in 1 are also studied at the same three levels of theory. In the σ-attack $S_N2$ transition state for 1 weak positive charge develops in the ring with X = F while negative charge develops with X = Cl and Br leading to a higher energy barrier with X = F but to lower energy barriers with X = Cl and Br than for the corresponding reactions of 2. The π-attack β-$S_N$2' transition states are stabilized by the strong $n_C-{\pi}^{*}_{C=C}$ charge transfer interactions, whereas the π-attack γ-$S_N$2' transition states are stabilized by the strong $n_C-{\sigma}^{*}_{C-X}$ interactions. For all types of reaction paths, the energy barriers are lower with X = F than Cl and Br due to the greater bond energy gain in the partial C-X bond formation with X = F. The β-$S_N$2' paths are favored over the γ-$S_N$2' paths only with X = F and the reverse holds with X = Cl and Br. The σ-attack $S_N2$ reaction provides the lowest energy barrier with X = Cl and Br, but that with X = F is the highest energy barrier path. Activation energies for the circumambulatory rearrangement processes are much higher (by more than 18 kcal $mol^{-1}$) than those for the corresponding $S_N2$ reaction path. Overall the gas-phase halide exchanges are predicted to proceed by the σ-attack $S_N2$ path with X = Cl and Br but by the β-$S_N$2'-anti path with X = F. The barriers to the gas-phase halide exchanges increase in the order X = F < Br < Cl, which is the same as that found for the gas-phase identity methyl transfer reactions.

• Journal of Ocean Engineering and Technology
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• v.3 no.2
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• pp.138-144
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• 1989

It has been very important in various industry fields to improve the fatigue strength characteristics of bearings such as bearing life, fatigue limit, etc., because such poor properties could result in shortening the machinery life as well as in decreasing the accuracy. However, no successful heat treatment criterion seems to be available at present. In this study, the effect of the $170^{\circ}C\times120min$ tempering cycles repeated after $380^{\circ}C\times80min$ oil quenching for $800^{\circ}C$ spheroidizing-annealed bearing steel (STB2) as base metal on the $120^{\circ}C$ high temperature rotary bending fatigue strength characteristics were investigated, including the effects on hardness, Charpy impact value and micro-structure, in order to seek for the best heat treatment condition finally. The important results obtained are as follows : 1) The optimal cycle of tempering so that the fatigue strength .sigma. could become the highest was the 4th cycle. And it is confirmed that this $\sigma_{F}$ is about 6 times more increased than that of base metal, and about 1.3 times more increased than the case of the 1 cycle tempered. 2) As a result of the investigation for the effects of tempering cycles on hardness, the hardness at the tempering number of 2 thru 5 cyles was not decreased severely ; only about 10% decrease from those of the quenched and 1 cycle tempered case. Such hardness is equivalent to $H_{R}$/C61-62 with no bad effect on anti-abrasion of bearing steel. 3) In the case of 2 thru 5 cycle tempering as well as 1 cycle tempering, the impact value was not so improved comparing with the case of quenching, but an increase of 5 to 10% could be expected at least. 4) It was experimentally confirmed that the control of the mechanical properties improvement such as fatigue strength and fatigue life for bearing steels could be possible by the number of tempering cycles.

• Journal of Ocean Engineering and Technology
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• v.3 no.2
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• pp.638-638
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• 1989

It has been very important in various industry fields to improve the fatigue strength characteristics of bearings such as bearing life, fatigue limit, etc., because such poor properties could result in shortening the machinery life as well as in decreasing the accuracy. However, no successful heat treatment criterion seems to be available at present. In this study, the effect of the $170^{\circ}C\times120min$ tempering cycles repeated after $380^{\circ}C\times80min$ oil quenching for $800^{\circ}C$ spheroidizing-annealed bearing steel (STB2) as base metal on the $120^{\circ}C$ high temperature rotary bending fatigue strength characteristics were investigated, including the effects on hardness, Charpy impact value and micro-structure, in order to seek for the best heat treatment condition finally. The important results obtained are as follows : 1) The optimal cycle of tempering so that the fatigue strength .sigma. could become the highest was the 4th cycle. And it is confirmed that this $\sigma_{F}$ is about 6 times more increased than that of base metal, and about 1.3 times more increased than the case of the 1 cycle tempered. 2) As a result of the investigation for the effects of tempering cycles on hardness, the hardness at the tempering number of 2 thru 5 cyles was not decreased severely ; only about 10% decrease from those of the quenched and 1 cycle tempered case. Such hardness is equivalent to $H_{R}$/C61-62 with no bad effect on anti-abrasion of bearing steel. 3) In the case of 2 thru 5 cycle tempering as well as 1 cycle tempering, the impact value was not so improved comparing with the case of quenching, but an increase of 5 to 10% could be expected at least. 4) It was experimentally confirmed that the control of the mechanical properties improvement such as fatigue strength and fatigue life for bearing steels could be possible by the number of tempering cycles.

• Journal of Animal Science and Technology
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• v.60 no.4
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• pp.9.1-9.11
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• 2018

Background: In recent years, with the prohibition of antibiotics used as growth stimulants in the nutrition of farm animals, researchers have searched for alternative natural and reliable products in order to be able to sustain the developments experienced during the use of antibiotics and to overcome the possible inconveniences. In this context, studies on evaluation of essential oils in poultry nutrition have been reported to improve the utilization of feed, stimulate the release of digestive enzymes, increase absorption in the stomach and intestines, antimicrobial and anti-parasitic effects and thus, can be an alternative to antibiotics and improve meat quality as well. Indeed, this study has been carried out to explore the effects of the addition of 150 mg/kg capsicum oleoresin (CAP), carvacrol (CAR), cinnamaldehyde (CIN) or their mixture (CAP+CAR+CIN) into the broilers' ration over sensory, physical and chemical properties in breast meat and leg meat. Methods: Experiments were conducted over 400 male and female broiler chicks (Ross-308) in 5 groups (1 control group and 4 treatment groups), each composed of 80 chicks. The control group was fed without feed additives while the second, third, fourth and the fifth groups were fed with 150 mg CAP/kg feed, 150 mg CAR/kg feed, 150 mg CIN/kg feed, and 150 mg CAP+CAR+CIN/kg feed, respectively. Results: Addition of CAP, CAR, CIN or CAP+CAR+CIN had effects on the sensory (of taste, tenderness, juiciness and overall acceptability); physical properties (of $L^*$ value and toughness), the chemical properties (of DM, CF, CP, linoleic, EPA, behenic, MUFA, PUFA and ${\Sigma}n-6$ of the leg meat), the physical characteristics (of toughness and firmness), and the chemical properties (of CF, CP, linoleic, ecosenic, EPA, lignoseric, MUFA and ${\Sigma}n-3$) of the breast meat in comparison to control group. Furthermore, while the treatments had positive impacts on thawing loss, cooking loss and water holding capacity in both breast and leg meat; no effect was observed on pH value and lipid oxidation on day 1, day 4 and day 8. Conclusion: The results strongly suggested that the addition of CAP, CAR, CIN or CAP+CAR+CIN to the rations of the broiler chicks changed the sensory, physical and chemical properties of breast and leg meat. It was also observed that these compounds were more effective when they were added to the ratio as a mixture rather than adding them individually.