Aerosol delivery of eukaryotic translation initiation factor 4E-binding protein 1 effectively suppresses lung tumorigenesis in K-ras^LA1 mice

Chang, S-H,Kim, J-E,Lee, J-H,Minai-Tehrani, A,Han, K,Chae, C,Cho, Y-H,Yun, J-H,Park, K,Kim, Y-S,Cho, M-H Nature America, Inc. 2013 Cancer gene therapy Vol.20 No.6

Conventional radiotherapy or chemotherapy for the long-term survival of patients with lung cancer is still difficult for treatment in metastatic and advanced tumors. Therefore, the safe and effective approaches to the treatment of lung cancer are needed. In this study, the effect of delivered eukaryotic translation initiation factor 4E (eIF4E)-binding protein 1 (4E-BP1) on lung cancer progression was evaluated. Recombinant adeno-associated virus (rAAV)-M3/4E-BP1 was delivered into 6-week-old K-ras<SUP>LA1</SUP> lung cancer model mice through a nose-only inhalation system twice a week for 4 weeks. Long-term repeated delivery of 4E-BP1 effectively reduced tumor progression in the lungs of K-ras<SUP>LA1</SUP> mice. Reduction of eIF4E by overexpression of 4E-BP1 resulted in suppression of cap-dependent protein expression of basic fibroblast growth factor (bFGF or FGF-2) and vascular endothelial growth factor (VEGF). In addition, delivered 4E-BP1 inhibited the proliferation of lung cancer cells in K-ras<SUP>LA1</SUP> mice model. Our results suggest that long-term repeated viral delivery of 4E-BP1 may provide a useful tool for designing lung cancer treatment.

X-ray Absorption and Emission Spectroscopic Studies of BiMn2-xTixO5 (0 ≤ x ≤ 0:5)

K. H. Chae,P. Thakur,황정남,G. S. Chang,D. K. Shukla,S. Mollah,Ravi Kumar 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.53 No.3

The electronic structure of the multiferroic BiMn2-xTixO5(0 ≤ x ≤ 0:5) system was studied by using X-ray absorption spectroscopy (XAS) and X-ray emission spectroscopy (XES). The polycrystalline bulk BiMn2-xTixO5 samples were synthesized using a conventional solid-state reaction technique. XAS and XES spectroscopic studies on the O K-, Mn K-, L3;2- and Ti L3;2-edges of the BiMn2-xTixO5 samples and of the reference compounds were performed and the results were compared in order to determine the exact chemical states of functioning ions. The O K-edge XAS and XES results demonstrate a competition between the Mn 3d and the Ti 3d orbitals on hybridizations with the O 2p orbital. The Mn K- and Mn L3;2-edge XAS spectra suggest that the Mn3+ /Mn4+ ratio increases with increasing Ti doping and drives the system towards octahedral symmetry. On the other hand, Ti ions remain at 4+ states for all compositions, as shown by the Ti L-edge XAS. Here, we present and discuss the detailed electronic structures of the BiMn2-xTixO5 samples.

DERIVATION OF UNCERTAINTY IMPORTANCE MEASURE AND ITS APPLICATION

Park, Chang K. 한국경영과학회 1990 한국경영과학회 학술대회논문집 Vol.- No.1

The uncertainty quantification process in probabilistic Risk Assessment usually involves a specification of the uncertainty in risk results. The distributional sensitivity analysis is to study the impact of the various assumptions made during the quantification of input parameter uncertainties on the final output uncertainty. The uncertainty important of input parameters, in this case, should reflect the degree of changes in the whole output distribution and not just in a point estimate value. A measure of the uncertainty importance is proposed in the present paper. The measure is called the distributional sensitivity measure (DSM) and explicitly derived from the definition of the Kullback's discrimination information. The DSM is applied to three typical cases of input distibutional changes: 1) Uncertainty is completely eliminated, 2) Uncertainty range is increased by a factor of 10, and 3) Type of distribution is changed. For all three cases of application, the DSM-based importance ranking agrees very well with the observed changes of output distribution while other statistical parameters are shown to be insensitive.

Point-Collocation Non-intrusive Polynomial Chaos 기법을 활용한 평판 주위 난류 유동장 해석

장경식(K. Chang),고아림(A.R. Ko) 한국전산유체공학회 2018 한국전산유체공학회지 Vol.23 No.2

In the present work, uncertainty quantification based on the point-collocation Non-intrusive Polynomial Chaos was studied in turbulent flow around the flat plate using Menter’s SST k-ω model. Two random variables of β* , model coefficient of Menter’s SST k-ω model and U<SUB>∞</SUB>, the freestream velocity are considered. β*, model coefficient was assumed to be uniformly distributed and the freestream velocity U<SUB>∞</SUB>, normally distributed with a certain value of variance. First, the uncertainty quantification with the single random variable of each one was simulated for sensitivity analysis of each parameter on the outputs such as drag coefficient and skin friction one. When the normal distribution of freestream velocity is considered, the drag coefficient showed the same type of distribution with 0.9% standard deviation. The uniform distribution of β* with the internals of 0.0784 and 0.1024 had an effect on 5% variance on drag coefficient. When two random variables are considered simultaneously, the distribution of drag coefficient showed closer type with one of model coefficient β* .The convergence rate of mean value was late than that with single random variable and standard deviation was not converged until the 5th order of gPC.

Comparison between a reanalyzed product by 3-dimensional variational assimilation technique and observations in the Ulleung Basin of the East/Japan Sea

Kim, Y.H.,Chang, K.I.,Park, J.J.,Park, S.K.,Lee, S.H.,Kim, Y.G.,Jung, K.T.,Kim, K. Elsevier 2009 Journal of marine systems Vol.78 No.2

Reanalyzed products from a MOM3-based East Sea Regional Ocean Model with a 3-dimentional variational data assimilation module (DA-ESROM), have been compared with the observed hydrographic and current datasets in the Ulleung Basin (UB) of the East/Japan Sea (EJS). Satellite-borne sea surface temperature and sea surface height data, and in-situ temperature profiles have been assimilated into the DA-ESROM. The performance of the DA-ESROM appears to be efficient enough to be used in an operational ocean forecast system. Comparing with the results from Mitchell et al. [Mitchell, D. A., Watts, D. R., Wimbush, M., Teague, W.J., Tracey, K. L., Book, J. W., Chang, K.-I., Suk, M.-S., Yoon, J.-H., 2005a. Upper circulation patterns in the Ulleung Basin. Deep-Sea Res. II, 52, 1617-1638.], the DA-ESROM fairly well simulates the high variability of the Ulleung Warm Eddy and Dok Cold Eddy as well as the branching of the Tsushima Warm Current in the UB. The overall root-mean-square error between 100 m temperature field reproduced by the DA-ESROM and the observed 100-dbar temperature field is 2.1 <SUP>o</SUP>C, and the spatially averaged grid-to-grid correlation between the two temperature fields is high with a mean value of 0.79 for the inter-comparison period. The DA-ESROM reproduces the development of strong southward North Korean Cold Current (NKCC) in summer consistent with the observational results, which is thought to be an improvement of the previous numerical models in the EJS. The reanalyzed products show that the NKCC is about 35 km wide, and flows southward along the Korean coast from spring to summer with maximum monthly mean volume transport of about 0.8 Sv in August-September.

Expression and Characterization of G Protein-activated Inward Rectifier $K^+$ Channels in Xenopus Oocytes

Kim, Han-Seop,Lee, Chang-Ho,Min, Churl K. The Korean Society for Integrative Biology 1998 Korean journal of biological sciences Vol.2 No.4

The G protein-activated inwardly rectifying $K^+$ channel (GIRK1) was coex-pressed in Xenopus oocytes along with the $5-HT_{1A}$ receptor, a 7-helix receptor known to be coupled to $K^+$ channels in many neural tissues. Thus, the activation of the $5-HT_{1A}$ receptor by its agonist leads to the opening of GIRK1. The GIRK1 current was measured using the two electrode voltage clamp technique with bath application of 5-HT in the presence of various external potassium concentrations $[K^+]_0$. GIRK1 showed a strong inward rectification since only hyperpolarizing voltages evoked inward currents. $K^{+}$ was the major ion carrier as evidenced by about 44㎷ voltage shift corresponding to a 10-fold external 〔$K^+$〕 change. 5-HT induced a concentration-dependent inward $K^+$ current ($EC_{50}{\equation omitted}10.7nM$) which was blocked by $Ba^{2+}$. Pertussis toxin (PTX) pre-treatment reduced the $K^+$ current by as much as about 70%, suggesting that PTX-sensitive G protein ($G_i or G_o$ type) are involved in the $5-HT_{1A}$ receptor-GIRK1 coupling in Xenopus oocytes.

Photoproduction of <tex> $ \Uplambda $</tex> and <tex> $ \Upsigma ^{0}$</tex> hyperons off protons with linearly polarized photons at <tex> $ E_{\gamma }=1.5\hbox{--}3.0$</tex> GeV

Shiu, S. H.,Kohri, H.,Chang, W. C.,Ahn, D. S.,Ahn, J. K.,Chen, J. Y.,Daté,, S.,Ejiri, H.,Fujimura, H.,Fujiwara, M.,Fukui, S.,Gohn, W.,Hicks, K.,Hotta, T.,Hwang, S. H.,Imai, K.,Ishikawa, T.,Joo, American Physical Society 2018 Physical Review C Vol.97 No.1

<P>We report the measurement of the gamma p -> K+Lambda and gamma p -> K+Sigma(0) reactions at SPring-8. The differential cross sections and photon-beam asymmetries are measured at forward K+ production angles using linearly polarized tagged-photon beams in the range of E-gamma = 1.5-3.0 GeV. With increasing photon energy, the cross sections for both gamma p -> K+Lambda and gamma p -> K+Sigma(0) reactions decrease slowly. Distinct narrow structures in the production cross section have not been found at E gamma = 1.5-3.0 GeV. The forward peaking in the angular distributions of cross sections, a characteristic feature of t-channel exchange, is observed for the production of Lambda in the whole observed energy range. A lack of similar feature for Sigma(0) production reflects a less dominant role of t-channel contribution in this channel. The photon-beam asymmetries remain positive for both reactions, suggesting the dominance of K* exchange in the t channel. These asymmetries increase gradually with the photon energy, and have a maximum value of +0.6 for both reactions. Comparison with theoretical predictions based on the Regge trajectory in the t channel and the contributions of nucleon resonances indicates the major role of t-channel contributions as well as non-negligible effects of nucleon resonances in accounting for the reaction mechanism of hyperon photoproduction in this photon energy regime.</P>

Temperature and air pollution affected tree ring δ¹³C and water-use efficiency of pine and oak trees under rising CO₂ in a humid temperate forest

Kwak, J.H.,Lim, S.S.,Lee, K.S.,Viet, H.D.,Matsushima, M.,Lee, K.H.,Jung, K.,Kim, H.Y.,Lee, S.M.,Chang, S.X.,Choi, W.J. Elsevier 2016 Chemical geology Vol.420 No.-

<P>To better predict forest productivity under rising atmospheric CO2 concentration ([CO2]), it is critical to understand how intrinsic water-use efficiency (WUEi) and its relationship with tree growth are affected by the concomitant changes in environmental conditions such as precipitation, temperature, and air pollution that either enhance or undermine any potential CO2 fertilization effect. We investigated changes in delta C-13 and WUEi in annual rings and basal area increment (BAI) of Pinus densiflora (from 1968 to 2007) and Quercus variabilis (from 1970 to 2007) trees in relation to precipitation, temperature, and air pollution in a humid temperate forest. The WUEi of P. densiflora increased by 39.9%, whereas that of Q. variabilis did not change over time in the study period. The WUEi was not affected by precipitation for both species but increased (P < 0.001) with temperature for P. densiflora and with SO2 emissions for both species. Multiple regression models suggested that the effect of [CO2] on tree growth was much higher than temperature; however, for the period (1998 to 2007) when SO2 emissions data were available, SO2 emission was the driver of changes in BAI and WUEi, and temperature effects became stronger than [CO2]. Overall, BAI and WUEi were positively (P < 0.001) correlated for P. densiflora, but not for Q. variabilis. We conclude that temperature and air pollution rather than precipitation were key determinants of WUEi at the study site and that the two species had contrasting responses to environmental changes. (C) 2015 Elsevier B.V. All rights reserved.</P>

Interference Effect betweenϕandΛ(1520)Production Channels in theγp→K+K−pReaction near Threshold

Ryu, S. Y.,Ahn, J. K.,Nakano, T.,Ahn, D. S.,Ajimura, S.,Akimune, H.,Asano, Y.,Chang, W. C.,Chen, J. Y.,Daté,, S.,Ejiri, H.,Fujimura, H.,Fujiwara, M.,Fukui, S.,Hasegawa, S.,Hicks, K.,Horie, K.,Ho American Physical Society 2016 Physical Review Letters Vol.116 No.23

<P>The phi-Lambda(1520) interference effect in the gamma p -> K(+)K(-)p reaction has been measured for the first time in the energy range from 1.673 to 2.173 GeV. The relative phases between phi and Lambda(1520) production amplitudes were obtained in the kinematic region where the two resonances overlap. The measurement results support strong constructive interference when K+K- pairs are observed at forward angles but destructive interference for proton emission at forward angles. Furthermore, the observed interference effect does not account for the root s = 2.1 GeV bump structure in forward differential cross sections for phi photoproduction. This fact suggests possible exotic structures such as a hidden-strangeness pentaquark state, a new Pomeron exchange, or rescattering processes via other hyperon states.</P>

Modulation of the MJO and North Pacific Storm Track Relationship by the QBO

Wang, Jiabao,Kim, Hye-Mi,Chang, Edmund K. M.,Son, Seok-Woo American Geophysical Union 2018 Journal of geophysical research. Atmospheres Vol.123 No.8

<P>This study demonstrates a possible impact of the quasi-biennial oscillation (QBO) on the Madden-Julian Oscillation (MJO)-related North Pacific storm track (NPST) change during October-March for the period of 1979-2016. The NPST shows significant intraseasonal changes in response to the MJO. In general, when the MJO convection is located over the Indian Ocean (western to central Pacific), the NPST tends to shift poleward (southward). This MJO-related NPST change has larger amplitude during the easterly phase of the QBO (EQBO) than during its westerly phase (WQBO). The spatial distribution of this NPST change also exhibits significant differences between the two QBO phases with a zonally elongated pattern during EQBO winters but separated into two centers during WQBO winters. Diagnoses of the dynamical processes associated with the NPST change indicate the dominant roles of the baroclinic energy conversion and downstream energy propagation. The analysis of intraseasonal flow change indicates a larger amplitude of the MJO-related baroclinicity over the North Pacific. This is likely due to a stronger MJO and associated Rossby wave source in EQBO winters, which may give rise to the enhanced amplitude of the NPST change. On the other hand, different spatial distribution of the NPST change is likely a result of a direct impact of the QBO on the NPST. These results suggest that the QBO impact needs to be considered for better reproduction of the MJO-NPST teleconnection in general circulation models, which may also benefit subseasonal prediction of extratropical storm activities.</P>