CircRNA PDE3B regulates tumorigenicity via the miR-136-5p/MAP3K2 axis of esophageal squamous cell carcinoma

Background. CircRNA has a covalently closed circular conformation and a stable structure. However, the exact role of circRNA in esophageal squamous cell carcinoma (ESCC) remains uncertain. The purpose of this study was to explore the role of hsa_circ_0000277 (circ_PDE3B) in ESCC. Methods. The expression levels of circ_PDE3B, miR-136-5p and mitogen-activated protein kinase kinase kinase 2 (MAP3K2) in ESCC tissues and cells were detected by quantitative real-time polymerase chain reaction (qRT-PCR) or western blot. The proliferation ability of EC9706 and KYSE30 cells was detected by clonal formation, 5-ethynyl-2’-deoxyuridine (EdU) and 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-Htetrazolium bromide (MTT) assays. Flow cytometry was used to detect the apoptosis rate of cells. Transwell assay was used to detect the invasion ability of EC9706 and KYSE3 cells. The relationship between miR-136-5p and circ_PDE3B or MAP3K2 was verified by dual-luciferase reporter assay and RNA pull-down, and the effect of circ_PDE3B on tumor growth in vivo was explored through tumor transplantation experiment. Immunohistochemistry (IHC) assay was used to detect MAP3K2 and Ki67 expression in mice tumor tissues. Results. The results showed that circ_PDE3B was highly expressed in ESCC tissues and cells. Downregulated circ_PDE3B expression in ESCC cells significantly reduced cell proliferation, migration and invasion. Circ_PDE3B served as a sponge for miR-136- 5p, and miR-136-5p inhibition reversed the roles of circ_PDE3B knockdown in ESCC cells. MAP3K2 was a direct target of miR-136-5p, and miR-136-5p targeted MAP3K2 to inhibit the malignant behaviors of ESCC cells. Furthermore, circ_PDE3B regulated MAP3K2 expression by sponging miR-136-5p. Importantly, circ_PDE3B knockdown inhibited tumor growth in vivo. Conclusions. In conclusion, circ_PDE3B acted as oncogenic circRNA in ESCC and accelerated ESCC progression by adsorption of miR-136-5p and activation of MAP3K2, supporting circ_PDE3B as a potential therapeutic target for ESCC

Ca(Mg1/3Ta2/3)O3 dielectric thin films: preparation, structure, mechanical and dielectric properties

The effects of annealing temperature on the crystallinity, grain size and hence mechanical and dielectric properties of Ca(Mg1/3Ta2/3)O3 (CMT) dielectric films were systematically studied. The CMT thin films were fabricated by an aqueous solution-gel technology and exhibited uniform, smooth and dense morphologies. The optimum pyrolysis temperature and time was 550 °C and 330 s, respectively. All the CMT films annealed from 650 to 800 °C show a single perovskite phase and the crystallization increases with increasing the annealed temperature but a secondary phase is observed in the film annealed at 900 °C. The hardness and reduced modulus were effectively enhanced by increasing the annealing temperature, which can be correlated to the crystallinity and densification improvements. Higher elastic recovery was observed for CMT films annealed at higher temperatures indicating less difficult recoveries for those films. We also noticed that the dielectric constants were improved for the samples annealed at higher temperature, which may enable higher performances for future microwave communication electronics

Some Results on Homogeneity Results for GLn

Let K be a nonarchimedian local field of characteristic zero with a ring of integers R and prime ideal p. Let G be a connected reductive algebraic group defined over K with Lie algebra g. In one of DeBacker's papers, he established a range of validity for the Harish-Chandra–Howe local expansion for characters of admissible irreducible representations of G under some conditions, and he established an analogous homogeneity result on the Lie algebra of G, again with some restrictions. These restrictions are, essentially, restrictions on the characteristic of the residue field k of K. While the hope of removing the characteristic restriction for G in general is not possible, in the case where G =GLn, we still have hope. Our primary goal here is to move towards a proof of a special type of case for a certain key step which plays a prominent role for the homogeneity result of GLn without characteristic restriction. Finally, In the end, I will also provide a full written proof for the homogeneity result of GL3.PHDMathematicsUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/172746/1/yiwchen_1.pd

Self-Assembled Conjugated Polyelectrolyte–Ionic Liquid Crystal Complex as an Interlayer for Polymer Solar Cells: Achieving Performance Enhancement via Rapid Liquid Crystal-Induced Dipole Orientation

A simple approach was demonstrated to manipulate dipole moment of interlayer in polymer solar cells (PSCs). The ionic liquid crystals (ILCs) 3-((2′-(4″-cyano­biphenyl-4-yloxy)­ethyl)­dimethyl­ammonio)­propane­sulfonate (CbpNSO) with zwitterionic charges were blended with cationic conjugated polyelectrolyte (CPE) poly­[3-(6-trimethylammoniumhexyl)­thiophene] (PTNBr) to afford a novel CPE–ILC complex. The water/alcohol solubility of the CPE–ILC complex enables it to be green solvent processable. The spontaneous orientation of liquid crystal (LC) favors more ordered structural arrangement in CPE–ILC complexes. More importantly, LC-assistant assembly improves the orientation of dipole at cathode and significantly reduces the work function of ITO. The power conversion efficiency (PCE) of P3HT:PC₆₀BM-based inverted PSCs with the layer of PTNBr–CbpNSO is increased by 37% with respect to that of the device with pure PTNBr. Incorporation of PTNBr–CbpNSO into the devices based on PBDTTT-C-T and PC₇₁BM affords a notable PCE of 7.49%. It should be noted that mesogens reduce the activation energy of molecular reorganization and accelerate dipole orientation in CPE–ILC interlayer under external electric field, which enables the dipole of this interlayer can be readily manipulated. Because of the rapid orientation of the dipole, PTNBr–CbpNSO shows reversible dipole at the active layer/ITO interface during the reversible bias process

Electrostatic Self-Assembled Metal Oxide/Conjugated Polyelectrolytes as Electron-Transporting Layers for Inverted Solar Cells with High Efficiency

Three conjugated polyelectrolytes (CPEs) based on polythiophenes bearing anionic (poly­[(3-(4′-sulfonatobutyl)­oxymethyl-2,5-thiophene)-<i>alt</i>-2,5-thiophene] sodium salt, PTSO-Na), neutral (HT-poly­[3-(6′-diethanolamino)-hexylthiophene], PTNOH) and cationic (HT-poly­[3-(6′-<i>N</i>,<i>N</i>,<i>N</i>-trimethylammonium)-hexylthiophene], PTN-Br) pendant groups were synthesized to improve the power conversion efficiency (PCE) of inverted polymer solar cells (I-PSCs) by deposition on the surface of ZnO to form a ZnO/CPE electron-transporting layer (ETL). Insertion of CPE to ZnO–active layer interfaces effectively lowered the energy barrier for electron transport and reduced the inherent incompatibility between the hydrophilic metal oxide and hydrophobic active layers. The I-PSCs (ITO/ZnO/CPE/P3HT:PCBM/PEDOT:PSS/Ag) incorporating anionic PTSO-Na achieved a 16% efficiency enhancement (PCE = 3.47%) over the standard device with a ZnO monolayer ETL (PCE = 2.99%). For the deposition of neutral PTNOH and cationic PTN-Br on top of ZnO, we observed strong electrostatic interaction between cationic quaternary amines of the CPE and anionic oxygen ions of the ZnO surfaces, which obtained a uniform formation of strong dipoles across the interfaces and an intimate interfacial contact. The self-assembly formed by partial protonation in neutral PTNOH increased the PCE of I-PSC to 3.98%, whereas the stronger electrostatic self-assembly produced in ZnO/PTN-Br bilayers not only delivered the device with the best PCE (4.08%) among the three CPEs but also yielded an exceptional device lifetime without encapsulation. It is worth noting that the performance of the I-PSC with PTN-Br already surpassed that of conventional ones (ITO/PEDOT:PSS/P3HT:PCBM/PTN-Br/LiF/Al). Moreover, the PCE of the device based on a ZnO/PTN-Br ETL was further improved to 4.45% after UV treatment with a 43% enhancement compared with the monolayer ZnO device, which is due to improved electrostatic self-assembly. These findings on electrostatic self-assembled metal oxide/CPE bilayer ETL provide a simple and easy strategy for fabrication of high-performance and long-term stable I-PSCs

Versatile Electron-Collecting Interfacial Layer by in Situ Growth of Silver Nanoparticles in Nonconjugated Polyelectrolyte Aqueous Solution for Polymer Solar Cells

Novel PEIE-Ag composites by in situ growth of silver nanoparticles in poly­(ethylenimine)-ethoxylated (PEIE) aqueous solution are explored as an efficient interfacial layer for improving inverted polymer solar cells (PSCs) performance. The hybrid PEIE-Ag interfacial material is simple to fabricate only via ultraviolet irradiation with good water-solubility and unique film formation. The generated Ag nanoparticles can anchor in the PEIE polymer chains to form a conductive continuous interpenetrating network structure. Combining of the advantages of PEIE and Ag nanoparticles, the PEIE-Ag shows enhanced charge transport, electron selective and collection, and improved light-harvesting, mainly due to the surface plasmon resonance effect, better energy alignment induced by the formation of ideal dipole layer, as well as the improved conductivity. These distinguished interfacial properties result in the power conversion efficiency of inverted PSCs based on poly­[4,8-bis­(2-ethyl-hexyl-thiophene-5-yl)-benzo­[1,2-b:4,5-b]­dithiophene-2,6-diyl]-<i>alt</i>-[2-(2-ethyl-hexanoyl)-thieno­[3,4-<i>b</i>]­thiophen-4,6-diyl] (PBDTTT-C-T) and [6,6]-phenyl C₇₁-butyric acid methyl ester (PC₇₁BM) photoactive layer substantially improved up to 7.66% from 6.11%. Moreover, the device performance is insensitively dependent on the thickness of the PEIE-Ag interfacial layer, broadening the thicknesses selection window for interfacial materials. These results demonstrate that PEIE-Ag is a potential interfacial material compatible with roll-to-roll techniques and suitable for printed electronic devices

ELECTROLESS PLATING OF COPPER ON POLYTETRAFLUOROETHYLENE FILMS MODIFIED BY SURFACE-INITIATED FREE RADICAL POLYMERIZATION OF 4-VINYLPYRIDINE

Surface modification of polytetrafluoroethylene (PTFE) films is done by exposing the films to a sodium naphthalenide (Na/naphtha) etchant, and esterification of 4,4'-azobis(4-cyanopentanoic acid) (ACP) with the hydroxyl groups covalently linked to the surface, followed by the surface-initiated free radical polymerization of 4-vinylpyridine (4 VP). The surface elemental composition and topography of the poly(4-vinylpyridine) (PVP) graft-functionalized PTFE surfaces (PTFE-g-PVP surfaces) were characterized by X-ray photoelectron spectroscopy (XPS), attenuated total reflectance (ATR) FTIR spectroscopy, and atomic force microscopy (AFM). Water contact angles on the pristine PTFE surface and PTFE-g-PVP surfaces were measured. The PVP brushes on the PTFE surface with well-preserved pyridine groups were used not only as the chemisorption sites for the palladium complexes (without the need for prior sensitization by SnCl2) during the electroless plating of copper, but also as an adhesion promotion layer to enhance the adhesion of the electrolessly deposited copper to the PTFE surfaces. The T-peel adhesion strength of the electrolessly deposited copper to the PVP grafted PTFE (PTFE-g-PVP) surface could reach about 7.2 N/cm. This adhesion strength was much higher than that of the electrolessly deposited copper to the pristine or Na/naphtha-treated PTFE surface. Effects of the graft polymerization time and the activation time in the PdCl2 solution on the T-peel adhesion strength of the electrolessly deposited copper (from the Sn-free process) to the PTFE-g-PVP surface were determined.Polyterafluoroethylene, 4-vinylpyridine, adhesion, electroless plating