Cold stress causes rapid but differential changes in properties of plasma membrane H⁺-ATPase of camelina and rapeseed

Kim, H.S.,Oh, J.M.,Luan, S.,Carlson, J.E.,Ahn, S.J. G. Fischer 2013 Journal of plant physiology Vol.170 No.9

Camelina (Camelina sativa) and rapeseed (Brassica napus) are well-established oil-seed crops with great promise also for biofuels. Both are cold-tolerant, and camelina is regarded to be especially appropriate for production on marginal lands. We examined physiological and biochemical alterations in both species during cold stress treatment for 3 days and subsequent recovery at the temperature of 25<SUP>o</SUP>C for 0, 0.25, 0.5, 1, 2, 6, and 24h, with particular emphasis on the post-translational regulation of the plasma membrane (PM) H<SUP>+</SUP>-ATPase (EC3.6.3.14). The activity and translation of the PM H<SUP>+</SUP>-ATPase, as well as 14-3-3 proteins, increased after 3 days of cold stress in both species but recovery under normal conditions proceeded differently. The increase in H<SUP>+</SUP>-ATPase activity was the most dramatic in camelina roots after recovery for 2h at 25<SUP>o</SUP>C, followed by decay to background levels within 24h. In rapeseed, the change in H<SUP>+</SUP>-ATPase activity during the recovery period was less pronounced. Furthermore, H<SUP>+</SUP>-pumping increased in both species after 15min recovery, but to twice the level in camelina roots compared to rapeseed. Protein gel blot analysis with phospho-threonine anti-bodies showed that an increase in phosphorylation levels paralleled the increase in H<SUP>+</SUP>-transport rate. Thus our results suggest that cold stress and recovery in camelina and rapeseed are associated with PM H<SUP>+</SUP>-fluxes that may be regulated by specific translational and post-translational modifications.

Advanced H2O2 oxidation for diethyl phthalate degradation in treated effluents: effect of nitrate on oxidation and a pilot-scale AOP operation

Ko, K. B.,Park, C. G.,Moon, T. H.,Ahn, Y. H.,Lee, J. K.,Ahn, K. H.,Park, J. H.,Yeom, I. T. IWA Publishing 2008 Water Science & Technology Vol.58 No.5

<P>One of the objectives of this study was to delineate the effect of nitrate on diethyl phthalate (DEP) oxidation by conducting a bench-scale ultraviolet (UV)/H2O2 and O3/H2O2 operations as suggested in a previous study. We also aim to investigate DEP oxidation at various UV doses and H2O2 concentrations by performing a pilot-scale advanced oxidation processes (AOP) system, into which a portion of the effluent from a pilot-scale membrane bioreactor (MBR) plant was pumped. In the bench-scale AOP operation, the O3 oxidation alone as well as the UV irradiation without H2O2 addition could be among the desirable alternatives for the efficient removal of DEP dissolved in aqueous solutions at a low DEP concentration range of 85±15 μg/L. The adverse effect in the UV/H2O2 process was significantly greater than that in the UV oxidation alone, and its oxidation was almost halved by the nitrate. However, the nitrate clearly enhanced the DEP oxidation in the O3 oxidation and O3/H2O2 process. Especially, the addition of nitrate almost doubled the DEP oxidation efficiency in the O3/H2O2 process. The series of pilot-scale AOP operations confirmed that about 30-50% of DEP dissolved in the treated MBR effluent streams was, at least, oxidized by the O3 oxidation alone as well as the UV irradiation without H2O2 addition. The UV photolysis of H2O2 was most effective for DEP degradation with an H2O2 concentration of 40 mg/L at a UV dose of 500 mJ/cm2.</P>

Effect of Tm3+ on the Strong Magnetic Anisotropy in the High-Tc Superconductor TmBa2Cu3Oy

J. H. Lee,김영철,D. Ahmad,김동진,정대영,I. S. Park,최민석,M. H. Sohn,장민수,Rock-Kil Ko,S. S. Ahn 한국물리학회 2007 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.50 No.4

The rare-earth superconductor TmBa2Cu3Ox(TmBCO) shows strong anisotropies in both para- magnetism and superconductivity. We discussed the eect of Tm3+ on the strong anisotropies of TmBCO. The magnetization (M) of TmBCO above the critical temperature (Tc) is very well described by the Brillouin function BJ (g¹BB=kBT) with J = 6, meaning that the paramagnetic signal of TmBCO is mainly generated from Tm3+ ions. The anisotropy of the magnetization values for T > Tc appears to be much stronger than that of YBCO. This can be explained by spin-orbit coupling of the two unpaired electrons of the Tm3+ ions in noncubic symmetry orbitals. From the superconducting signal below Tc, an anisotropy of the critical current density (Jcjj < Jc?) has been observed, where Jcjj and Jc? are the critical current densities measured under a .eld applied parallel to the c-axis (Hjj) and a .eld applied parallel to the ab-plane (H?), respectively. The super- conducting anisotropy can be explained by the local .eld intensity on the Cu-O planes depending on the spin alignment direction of the two unpaired electrons of the Tm3+ ion determined by H. In addition, Jc?(H) for H > 20 kOe increased a little as H increased, showing non-collective °ux pinning behavior. This means that the Tm3+ ions under H? serve as pinning centers in high .elds.ame=JP0

Increase in Trx2/Prx3 redox system immunoreactivity in the spinal cord and hippocampus of aged dogs

Ahn, J.H.,Choi, J.H.,Song, J.M.,Lee, C.H.,Yoo, K.Y.,Hwang, I.K.,Kim, J.S.,Shin, H.C.,Won, M.H. Pergamon Press ; Elsevier Science Ltd 2011 Experimental Gerontology Vol.46 No.11

We previously reported that no distinct neuronal loss occurred in the aged dog spinal cord, although oxidative stress was increased in the aged dog spinal cord. Thioredoxin 2 (Trx2)/peroxiredoxin 3 (Prx3) redox system is a major route for removing H<SUB>2</SUB>O<SUB>2</SUB> in the central nervous system. In the present study, we compared the distribution and immunoreactivity of thioredoxin reductase 2 (TrxR2), Trx2 and Prx3 and their protein levels in the spinal cord and hippocampus between the adult (2-3years) and aged (10-12years) dogs. The number of TrxR2-immunoreactive neurons was slightly increased; however, its immunoreactivity was significantly increased in the aged spinal cord compared to that in the adult spinal cord. On the other hand, the number and immunoreactivity of both Trx2- and Prx3-immunoreactive neurons were significantly increased in the spinal cord of the aged dog. Similarly, in the hippocampus of the aged dog, TrxR2, Trx2 and Prx3 immunoreactivity and protein levels were markedly increased compared to those in the adult dog. These results indicate that the increases of TrxR2, Trx2 and Prx3 immunoreactivity and their protein levels in the aged spinal cord and hippocampus may contribute to reducing neuronal damage against oxidative stresses during normal aging.

Jatropha is vulnerable to cold injury due to impaired activity and expression of plasma membrane H+-ATPase

Oh, J. M.,Kim, H. S.,Bae, H. J.,Ahn, S. J. POLISH ACADEMY SCIENCES WARSAW 2014 ACTA PHYSIOLOGIAE PLANTARUM Vol.36 No.1

Cold stress is one of the major environmental factors limiting the amount of plant mass for bioenergy production. A chilling-sensitive Jatropha (Jatropha curcas L.) as a bioenergy crop was used to investigate the cold injury process at the physiological and biochemical levels. Various physiological parameters such as leaf length, width, stomatal conductance, chlorophyll fluorescence, and electrolyte leakage were measured to determine the growth rate of leaves cold-treated (7 and 2 A degrees C) for 5 days. These parameters of cold-treated Jatropha were significantly reduced from day 1 compared with control (23 A degrees C). Using the pH indicator bromocresol purple, it was shown that surface pH of Jatropha root in control was strongly acidified by time only from the starting pH 6, while H+-efflux of the surface of cold-treated roots did not change. H+-ATPase activity of plasma membrane (PM) isolated from leaves and roots of cold-treated Jatropha was decreased in a time-dependent manner. The expression of PM H+-ATPase and 14-3-3 protein, which participates in phosphorylation of PM H+-ATPase was reduced in the presence of cold stress. Interestingly, fusicoccin, an activator of the PM H+-ATPase, alleviated cold-injury by stimulating the enzyme in leaves. These results may suggest that the activity and expression of PM H+-ATPase in Jatropha is closely related to the overcoming of cold stress.

Effects of Egg Yolk Antibodies Produced in Response to Different Antigenic Fractions of E. coli O157:H7 on E. coli Suppression

Chae, H.S.,Singh, N.K.,Ahn, C.N.,Yoo, Y.M.,Jeong, S.G.,Ham, J.S.,Kim, D.W. Asian Australasian Association of Animal Productio 2006 Animal Bioscience Vol.19 No.11

The objective of this research was to provide the characterization and method for producing anti-E. coli O157:H7 antibodies in egg-laying hens and to determine if the antibody can restrain the proliferation of E. coli O157:H7 in-vitro. Selected antigenic fractions (whole cell, outer membrane protein and lipopolysaccharide (LPS)) from E. coli O157:H7 were injected to hens in order to produce anti-E. coli O157:H7 antibodies. The immune response and the egg yolk antibodies of laying hens against the whole cell, outer membrane protein and LPS antigens were monitored by ELISA. The level of antibodies against whole cell antigen monitored through ELISA sharply increased after the initial immunization, and it was found to be maximum on day 49 however, the level was maintained up to day 70. Antibodies (5 mg/ml) directed against the whole cell inhibited E. coli proliferation 10-13 times more than outer membrane protein or LPS. The antibody response against the whole cell antigens appeared to have higher activity in restraining the proliferation of E. coli O157:H7 than antibody against outer membrane protein or LPS. Results reflected that increasing the IgY's in the egg yolk could prevent greater economic losses due to human and animal health from pathogenic bacteria i.e. E. coli O157:H7.

NPS2143 Inhibits MUC5AC and Proinflammatory Mediators in Cigarette Smoke Extract (CSE)-Stimulated Human Airway Epithelial Cells

Lee, J. W.,Park, J. W.,Kwon, O. K.,Lee, H. J.,Jeong, H. G.,Kim, J. H.,Oh, S. R.,Ahn, K. S. Springer Science + Business Media 2017 INFLAMMATION Vol.40 No.1

<P>Mucus overproduction is a fundamental hallmark of COPD that is caused by exposure to cigarette smoke. MUC5AC is one of the main mucin genes expressed in the respiratory epithelium, and its transcriptional upregulation often correlates with increased mucus secretion. Calcium-sensing receptor (CaSR) antagonists have been reported to possess anti-inflammatory effects. The purpose of the present study was to investigate the protective role of NPS2143, a selective CaSR antagonist on cigarette smoke extract (CSE)-stimulated NCI-H292 mucoepidermoid human lung cells. Treatment of NPS2143 significantly inhibited the expression of MUC5AC in CSE-stimulated H292 cells. NPS2143 reduced the expression of MMP-9 in CSE-stimulated H292 cells. NPS2143 also decreased the release of proinflammatory cytokines such as IL-6 and TNF-alpha in CSE-stimulated H292 cells. Furthermore, NPS2143 attenuated the activation of MAPKs (JNK, p38, and ERK) and inhibited the nuclear translocation of NF-kappa B in CSE-stimulated H292 cells. These results indicate that NPS2143 had a therapeutic potential in COPD.</P>

Role of n-type seed-layers in microstructural evolution of intrinsic nanocrystalline silicon and solar cell performance

Lee, J.E.,Ahn, S.,Park, J.H.,Yoo, J.,Yoon, K.H.,Kim, D.,Cho, J.S. Elsevier 2013 CURRENT APPLIED PHYSICS Vol.13 No.7

Nanocrystalline silicon (nc-Si:H) thin-film n-i-p solar cells were constructed on flexible stainless steel substrates by plasma-enhanced chemical vapor deposition. Influence of the n-type seed-layer on the microstructural evolution of the subsequent intrinsic nc-Si:H absorbers and the resultant performance of nc-Si:H solar cells was investigated. The crystalline volume fraction of the seed-layer can be effectively controlled by varying the hydrogen (H<SUB>2</SUB>) to silane (SiH<SUB>4</SUB>) gas flow ratio. Defect-dense amorphous regions were observed at the initial growth stage of the i-layers deposited on low crystalline volume fraction (X<SUB>c</SUB><SUP>n</SUP>) n-type seed-layers. Increasing the X<SUB>c</SUB><SUP>n</SUP> reduced the amorphous region at the n/i interface of the i nc-Si:H layers, evidenced by Raman scattering and transmission electron microscopy (TEM) measurements. Elimination of the defect-rich amorphous region within the i-layer by depositing the nc-Si:H solar cells on highly crystalline seed-layer caused significant improvements in the short circuit current density (J<SUB>sc</SUB>) and fill factor (FF). This is mainly due to the enhancement of long-wavelength light response and extraction efficiency of photo-carrier charges. The nc-Si:H solar cells prepared on a highly crystalline seed-layer (X<SUB>c</SUB><SUP>n</SUP>=73%) exhibited a 65.6% higher conversion efficiency than those on the n-type amorphous layers (X<SUB>c</SUB><SUP>n</SUP>=0%).

건국 우유와 유제품의 소비성향에 관한 조사연구

임종우,김종우,조광호,김영주,유제현,윤여창,장주익,권일경,안효일,이용규,이부응,박종래,이헌종 경상대학교 축산진흥연구소 1989 畜産振興硏究所報 Vol.16 No.1

3상 H-bridge Multi-level inverter의 변형된 SVM에 관한 연구

엄준현(J. H. Eum),안현진(H. J. Ahn),정영국(Y. G. Jung),임영철(Y. C. Lim),김광헌(K. H. Kim),차득근(D. G. Cha) 전력전자학회 2009 전력전자학술대회 논문집 Vol.2009 No.1

As H-bridge multilevel inverter is connected with series of single phase power cell, so it obtain high voltage using low voltage power semi-conductor and output voltage similar to sinusoidal wave. In this topology, the number of power cell increases in proportion to the output voltage level. This paper proposes a H-bridge Multilevel inverter and SVM(Space Vector Modulation) using slope of a linear function. The proposed method has some features improves processing of system, and decreases THD, and reduces to switching loss. To verify a validity of proposed method a PSIM simulation is used.