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Calsenilin regulates presenilin 1/γ‐secretase‐mediated N‐cadherin ∊‐cleavage and β‐catenin signaling
Jang, Changhwan,Choi, Jinx2010,Kyu,Na, Yeox2010,Jung,Jang, Byungki,Wasco, Wilma,Buxbaum, Joseph D.,Kim, Yongx2010,Sun,Choi, Eunx2010,Kyoung Federation of American Society for Experimental Bi 2011 The FASEB Journal Vol.25 No.12
<P>Presenilin 1 (PS1) is a component of the γ-secretase complex that cleaves a variety of type I membrane proteins, including the β-amyloid precursor protein (β-APP), Notch, and neuronal (N)- and epithelial (E)-cadherins. N-cadherin is an essential adhesion molecule that forms a complex with, and is cleaved by, PS1/γ-secretase and β-catenin in the plasma membrane. The purpose of this study was to determine whether calsenilin, a presenilin-interacting protein, has a functional role in PS1/γ-secretase-mediated N-cadherin ε-cleavage using Western blot analysis, RT-PCR, immunoprecipitation, subcellular fractionation, biotinylation, and a luciferase reporter assay in SH-SY5Y neuroblastoma cells. Here, we demonstrate that the expression of calsenilin leads to a disruption of PS1/γ-secretase-mediated ε-cleavage of N-cadherin, which results in the significant accumulation of N-cadherin C-terminal fragment 1 (Ncad/CTF1), the reduction of cytoplasmic Ncad/CTF2 release, and a deceleration of PS1-CTF delivery to the cell surface. Interestingly, we also found that the expression of calsenilin is associated with the redistribution of β-catenin from the cell surface to a cytoplasmic pool, as well as with the negative regulation of genes that are targets of T-cell factor/β-catenin nuclear signaling. Taken together, our findings suggest that calsenilin is a novel negative regulator of N-cadherin processing that plays an important role in β-catenin signaling.</P>
Sun, G.A.,Wang, X.L.,Wang, Y.D.,Woo, W.C.,Wang, H.,Liu, X.P.,Chen, B.,Fu, Y.Q.,Sheng, L.S.,Ren, Y. Elsevier Sequoia 2013 Materials science & engineering. properties, micro Vol.560 No.-
High-energy synchrotron X-ray diffraction technique was used to in-situ characterize microstructure, lattice strain, and phase transition behavior of a Ni<SUB>47</SUB>Ti<SUB>44</SUB>Nb<SUB>9</SUB> shape memory alloy. Phase transformation kinetics and deformation mechanisms were studied under a uniaxial tension at three testing temperatures, i.e., -70<SUP>o</SUP>C, 25<SUP>o</SUP>C, and 150<SUP>o</SUP>C. At a testing temperature of -70<SUP>o</SUP>C, a complicated phase transformation with four stages of micromechanical deformation was identified which is associated with changes of martensite substructures. At room temperature of 25<SUP>o</SUP>C, there was no stress-induced selection process of variants of B19' phases observed. Whereas at a testing temperature of 150<SUP>o</SUP>C, there was no any phase transformation observed. It is verified that β-Nb phase, an effective stabilizer for the austenite, delays the process of martensitic transformation and relaxes the strain energy without strengthening the matrix. This new finding is important to understand the relationship between the micromechanical deformation behavior and phase transformations in the Ni<SUB>47</SUB>Ti<SUB>44</SUB>Nb<SUB>9</SUB> SMA.
Jo, Jang,Pouliot, Jeanx2010,Ré,mi,Wynands, David,Collins, Samuel D.,Kim, Jin Young,Nguyen, Thanh Luan,Woo, Han Young,Sun, Yanming,Leclerc, Mario,Heeger, Alan J. WILEY‐VCH Verlag 2013 ADVANCED MATERIALS Vol.25 No.34
<P><B>Power conversion efficiency up to 8.6%</B> is achieved for a solution‐processed tandem solar cell based on a diketopyrrolopyrrole‐containing polymer as the low‐bandgap material after using a thin polyelectrolyte layer to modify the electron‐transport ZnO layers, indicating that interfacial engineering is a useful approach to further enhancing the efficiency of tandem organic solar cells.</P>
Pre-sodiated nickel cobaltite for high-performance sodium-ion capacitors
Yang, D.,Sun, X.,Lim, K.,Ranganathan Gaddam, R.,Ashok Kumar, N.,Kang, K.,Zhao, X.S. Elsevier Sequoia 2017 Journal of Power Sources Vol.362 No.-
Sodium-ion capacitors (NICs) are a hybrid energy storage system that store energy via both charge adsorption at the cathode/electrolyte interface and charge intercalation in the bulk of the anode, thereby possessing a higher energy density than supercapacitors and a higher power density than batteries. In this work, nickel cobaltite (NiCo<SUB>2</SUB>O<SUB>4</SUB>) hollow spheres with a chestnut shell morphology have been solvothermally synthesized and tested in a sodium half-cell. The NiCo<SUB>2</SUB>O<SUB>4</SUB> material exhibits a reversible capacity of 313 mAh g<SUP>-1</SUP> at 1 A g<SUP>-1</SUP>. Pre-sodiation of NiCo<SUB>2</SUB>O<SUB>4</SUB> is found to significantly improve its energy density. A NIC fabricated with pre-sodiated NiCo<SUB>2</SUB>O<SUB>4</SUB> as the anode and an activated carbon (AC) as the cathode delivers an energy density of 60 Wh kg<SUP>-1</SUP> at the power density of 10,000 W kg<SUP>-1</SUP>. Ex-situ X-ray diffraction (XRD) and transmission electron microscopy (TEM) results reveal that NiCo<SUB>2</SUB>O<SUB>4</SUB> is converted to metallic nickel and cobalt and Na<SUB>2</SUB>O phases during the pre-sodiation. The metallic nickel and cobalt phases are kinetically favourable for the electrolyte diffusion and electrochemical reactions, thus significantly improving the performance of the pre-sodiated NiCo<SUB>2</SUB>O<SUB>4</SUB> electrode.
Hydrodynamics and simulation of air–water homogeneous bubble column under elevated pressure
Tran, Bay V.,Nguyen, Dan D.,Ngo, Son I.,Lim, Youngx2010,Il,Kim, Bongjun,Lee, Dong Hyun,Go, Kangx2010,Seok,Nho, Namx2010,Sun American Institute of Chemical Engineers 2019 AIChE Journal Vol.65 No.10
<P><B>Abstract</B></P><P>A gas–liquid Eulerian computational fluid dynamics (CFD) model coupled with a population balance equation (PBE) was presented to investigate hydrodynamics of an air–water bubble column (1.8 m in height and 0.1 m in inner diameter) under elevated pressure in terms of pressure drop, gas holdup, mean bubble size, and bubble surface area. The CFD‐PBE model was modified with three pressure correction factors to predict both the total gas holdup and the mean bubble size in the homogeneous bubbly flow regime. The three correction factors were optimized compared to experimental data. Increasing the pressure led to increasing the density, reducing the bubble size, and increasing the gas holdup. The bubble size distribution moved toward a smaller bubble size, as the pressure increased. The modified CFD‐PBE model validated with experimental data and empirical models represented well hydrodynamics of the bubble column at <I>P</I> = 0.1, 1.5, and 3.5 MPa.</P>
Ivanchikova, Irina D.,Lee, Ji Sun,Maksimchuk, Nataliya V.,Shmakov, Alexander N.,Chesalov, Yurii A.,Ayupov, Artem B.,Hwang, Young Kyu,Jun, Chulx2010,Ho,Chang, Jongx2010,San,Kholdeeva, Oxana A. Wiley-VCH 2014 European journal of inorganic chemistry Vol. No.
<P><B>Abstract</B></P><P>The titanium‐based metal–organic framework MIL‐125 and its amine‐functionalized analog, MIL‐125_NH<SUB>2</SUB>, have been synthesized and characterized by elemental analysis, XRD, SEM, TEM, N<SUB>2</SUB> adsorption measurements, and spectroscopic techniques, including FTIR, Raman, and DR UV/Vis spectroscopy. Catalytic properties of MIL‐125 and MIL‐125_NH<SUB>2</SUB> were evaluated in the selective oxidation of two representative alkyl‐substituted phenols, 2,3,6‐trimethylphenol and 2,6‐di‐<I>tert</I>‐butylphenol, with the clean oxidant H<SUB>2</SUB>O<SUB>2</SUB>. With both MIL‐125 and MIL‐125_NH<SUB>2</SUB>, the selectivity toward the corresponding <I>p</I>‐benzoquinones was 100 %. Samples of MIL‐125 with different sizes of crystallites (0.5, 1.5, and 5 μm) demonstrated similar reaction rates, thus indicating the absence of diffusion limitations. The efficiency of the oxidant utilization and stability of the MIL‐125 structure increased upon decreasing the amount of water in the reaction mixture. Even if the structural integrity of MIL‐125 was destroyed by the reaction medium, the metal–organic framework acted as a precursor for the highly active, selective, and recyclable catalyst. The MIL‐125‐derived materials were stable toward titanium leaching, behaved as true heterogeneous catalysts, and could easily be recovered by filtration and reused several times without the loss of the catalytic properties.</P>
Li, Yuan,Heng, Wee-Kuan,Lee, Byung Sun,Aratani, Naoki,Zafra, Josex301,L.,Bao, Nina,Lee, Richmond,Sung, Young Mo,Sun, Zhe,Huang, Kuo-Wei,Webster, Richard D.,Lox301,pez Navarrete, Juan T.,Kim, Dongh American Chemical Society 2012 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.134 No.36
<P>Polycyclic aromatic hydrocarbons with an open-shell singlet biradical ground state are of fundamental interest and have potential applications in materials science. However, the inherent high reactivity makes their synthesis and characterization very challenging. In this work, a convenient synthetic route was developed to synthesize two kinetically blocked heptazethrene (<B>HZ-TIPS</B>) and octazethrene (<B>OZ-TIPS</B>) compounds with good stability. Their ground-state electronic structures were systematically investigated by a combination of different experimental methods, including steady-state and transient absorption spectroscopy, variable temperature NMR, electron spin resonance (ESR), superconducting quantum interfering device (SQUID), FT Raman, and X-ray crystallographic analysis, assisted by unrestricted symmetry-broken density functional theory (DFT) calculations. All these demonstrated that the heptazethrene derivative <B>HZ-TIPS</B> has a closed-shell ground state while its octazethrene analogue <B>OZ-TIPS</B> with a smaller energy gap exists as an open-shell singlet biradical with a large measured biradical character (<I>y</I> = 0.56). Large two-photon absorption (TPA) cross sections (σ<SUP>(2)</SUP>) were determined for <B>HZ-TIPS</B> (σ<SUP>(2)</SUP><SUB>max</SUB> = 920 GM at 1250 nm) and <B>OZ-TIPS</B> (σ<SUP>(2)</SUP><SUB>max</SUB> = 1200 GM at 1250 nm). In addition, <B>HZ-TIPS</B> and <B>OZ-TIPS</B> show a closely stacked 1D polymer chain in single crystals.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/2012/jacsat.2012.134.issue-36/ja304618v/production/images/medium/ja-2012-04618v_0015.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ja304618v'>ACS Electronic Supporting Info</A></P>
J. He,Q.Z. Cai,D. Zhu,Q. Luo,D.Q. Zhang,X.W. Li,X. Zhao,W. Sun 한국물리학회 2011 Current Applied Physics Vol.11 No.1
A WO_3/TiO_2 composite film was in-situ prepared in tungstate electrolyte and characterized by Electron microscopy, X-ray diffraction, UV―Vis spectrophotometer and Photoluminescence. The oxide film consists of mixture phases of anatase and rutile, showing porous structures and metallurgical bond with substrate. With the incorporation of WO_3 into TiO_2, the optical absorption edge of TiO_2 filmwas shifted to longer wavelength slightly and the separation between electrons and holes was promoted effectively. WO_3/TiO_2 composite film with increased photo quantum efficiency will be promising in the treatment of environmental pollutants.
Formation and characterization of polylactide and β-cyclodextrin inclusion complex
D.M. Xie,K.S. Yang,W.X. Sun 한국물리학회 2007 Current Applied Physics Vol.7 No.s1
Inclusion complex (ICs) ofb-cyclodextrin (bshowed that the feeding ratios ofb-CD and PLA and the molecular weight of PLA had signicant eects on the formation of theICs, and the formed ICs could be dispersed in water when the molecular number weight (Mn) of PLA was lower than 100,000, whereasthey agglomerated when the Mn of PLA reached 500,000 or more. The structures of the ICs were veried by Fourier transform infrared(FTIR) spectroscopy, dierential scanning calorimetry (DSC), and wide-angle X-ray diraction (WAXD). Results for surface contactmetric analysis (TGA) indicated that the ICs had a lower glass transition temperature than pure PLA had. The ICs of PLA andb-CDshow great potential as tissue engineering scaold.
Lee, Young Sun,Beers, Timothy C.,An, Deokkeun,Ivezix107,, x17d,eljko,Just, Andreas,Rockosi, Constance M.,Morrison, Heather L.,Johnson, Jennifer A.,Schö,nrich, Ralph,Bird, Jonathan,Yanny, Brian IOP Publishing 2011 The Astrophysical journal Vol.738 No.2
<P>We employ measurements of the [alpha/Fe] ratio derived from low-resolution (R similar to 2000) spectra of 17,277 G-type dwarfs from the SEGUE survey to separate them into likely thin-and thick-disk subsamples. Both subsamples exhibit strong gradients of orbital rotational velocity with metallicity, of opposite signs, -20 to -30 km s(-1) dex(-1) for the thin-disk and + 40 to + 50 km s(-1) dex(-1) for the thick-disk population. The rotational velocity is uncorrelated with Galactocentric distance for the thin-disk subsample and exhibits a small trend for the thick-disk subsample. The rotational velocity decreases with distance from the plane for both disk components, with similar slopes (-9.0 +/- 1.0 km s(-1) kpc(-1)). Thick-disk stars exhibit a strong trend of orbital eccentricity with metallicity (about -0.2 dex(-1)), while the eccentricity does not change with metallicity for the thin-disk subsample. The eccentricity is almost independent of Galactocentric radius for the thin-disk population, while a marginal gradient of the eccentricity with radius exists for the thick-disk population. Both subsamples possess similar positive gradients of eccentricity with distance from the Galactic plane. The shapes of the eccentricity distributions for the thin-and thick-disk populations are independent of distance from the plane, and include no significant numbers of stars with eccentricity above 0.6. Among several contemporary models of disk evolution that we consider, radial migration appears to have played an important role in the evolution of the thin-disk population, but possibly less so for the thick disk, relative to the gas-rich merger or disk heating scenarios. We emphasize that more physically realistic models and simulations need to be constructed in order to carry out the detailed quantitative comparisons that our new data enable.</P>