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91.
There is a growing need for the development of in vitro 3D cell culture models for assessing newer therapeutics for clinical applications and mechanisms of human pathology. Molecular beacons have been successfully delivered in two-dimensional (2D) systems to monitor, detect, and localize specific mRNA expression in living cells at the single cell level. However, to date the use of molecular beacons in three-dimensional (3D) systems has not been reported. To translate this technology into specific clinical targeted applications, it is critical to develop and demonstrate efficacy in a 3D system. For the first time the use of TAT-peptide conjugated molecular beacons to monitor mRNA in a 3D in vitro system has been reported. 相似文献
92.
Emmanuel Sopbué Fondjo Joseph Tsemeugne Beibam Luc Sondengam Thomas Oppenlaender Hippolyte Kamdem Wabo Pierre Tane Joseph D. Connolly Wim Dehaen Taoufik Rohand Haruhisa Kikuchi Yoshiteru Oshima 《Journal of heterocyclic chemistry》2011,48(6):1295-1301
The coupling reactions of two diazotized 3‐aminothieno[3,4‐c]coumarins were investigated. Compounds 1a , 1b both react with sodium nitrite in concentrated sulphuric acid at 0–5°C to give the diazotized intermediates 2 and 3 , the latter resulting from the acid ‐catalyzed hydrolysis of the lactonic ring of 2 . The in situ formed diazonium salts react with aromatic amines ( 4 ) to afford a series of arylazothiophenes dyes in the form of their ammonium sulfate salts. With diazotized aniline, besides the normally expected phenylazothiophene 10 from the reaction with compound 1a , the corresponding product of acid hydrolysis 11 was also isolated. In at least one of the cases, the thienyl diazonium salt 2 undergoes a Gomberg–Bachmann arylation reaction with p‐nitroaniline to give the 2‐arylthiophene 9 . The direct hydrolysis of compounds 1a , 1b by concentrated sulphuric acid and subsequent oxidative dimerization of the primary product of acid hydrolysis led to compound 12 . J. Heterocyclic Chem., (2011). 相似文献
93.
K.P. Somers J.M. Simmie F. Gillespie U. Burke J. Connolly W.K. Metcalfe F. Battin-Leclerc P. Dirrenberger O. Herbinet P.-A. Glaude H.J. Curran 《Proceedings of the Combustion Institute》2013,34(1):225-232
An experimental ignition delay time study for the promising biofuel 2-methyl furan (2MF) was performed at equivalence ratios of 0.5, 1.0 and 2.0 for mixtures of 1% fuel in argon in the temperature range 1200–1800 K at atmospheric pressure. Laminar burning velocities were determined using the heat-flux method for mixtures of 2MF in air at equivalence ratios of 0.55–1.65, initial temperatures of 298–398 K and atmospheric pressure. A detailed chemical kinetic mechanism consisting of 2059 reactions and 391 species has been constructed to describe the oxidation of 2MF and is used to simulate experiment. Accurate reproduction of the experimental data has been obtained over all conditions with the developed mechanism. Rate of production and sensitivity analyses have been carried out to identify important consumption pathways of the fuel and key kinetic parameters under these conditions. The reactions of hydrogen atom with the fuel are highlighted as important under all experimental conditions studied, with abstraction by the hydrogen atom promoting reactivity and hydrogen atom addition to the furan ring inhibiting reactivity. This work, to the authors knowledge, is the first to combine theoretical and experimental work to describe the oxidation of any of the alkylated furans. The mechanism developed herein to describe 2MF combustion should also function as a sub-mechanism to describe the oxidation of 2,5-dimethyl furan whilst also providing key insights into the oxidation of this similar biofuel candidate. 相似文献
94.
Marco Zecca Sarah J. Vogt Paul R. J. Connolly Eric F. May Michael L. Johns 《Transport in Porous Media》2018,125(2):271-288
The tortuosity (τ), defined in the present context as the ratio of the free diffusion coefficient to the restricted diffusion coefficient of a contained fluid, is an important but difficult to measure characteristic of a porous medium, particularly when it is partially saturated with water. We develop and apply methodology, based on nuclear magnetic resonance (NMR) pulsed field gradient techniques, to measure τ for various sandstone rock cores as a function of residual water fraction. The NMR methodology requires the use of bipolar pulsed field gradient stimulated echo pulse sequences to avoid systematic errors due to magnetic susceptibility differences and D2O as a stationary immiscible water phase; this was selected as it provides no 1H NMR signal. Tortuosity of the free pore space was successfully measured using liquid ethane as a probe fluid for three different sandstones over the full accessible range of residual water saturation. Generally, the tortuosity was observed to increase with residual water (D2O) content; however, significant variations were observed between the different sandstones. 相似文献
95.
Yong Huang Alexandre Gheno Alain Rolland Laurent Pedesseau Sylvain Vedraine Olivier Durand Johann Bouclé James P. Connolly Lioz Etgar Jacky Even 《Optical and Quantum Electronics》2018,50(1):41
A numerical method is proposed to model Kelvin probe force microscopy of hetero-structures in the dark and under illumination. It is applied to FTO/TiO2 and FTO/TiO2/MAPbI3 structures. The presence of surface states on the top of the TiO2 layers are revealed by combining theoretical computation and experimental results. Basic features of Kelvin probe force microscopy under illumination, namely surface photovoltage, are simulated as well. The method paves the way toward further investigations of more complicated optoelectronic devices. 相似文献
96.
Abbasi RU Abu-Zayyad T Allen M Amman JF Archbold G Belov K Belz JW Ben Zvi SY Bergman DR Blake SA Brusova OA Burt GW Cannon C Cao Z Connolly BC Deng W Fedorova Y Finley CB Gray RC Hanlon WF Hoffman CM Holzscheiter MH Hughes G Hüntemeyer P Jones BF Jui CC Kim K Kirn MA Loh EC Maestas MM Manago N Marek LJ Martens K Matthews JA Matthews JN Moore SA O'Neill A Painter CA Perera L Reil K Riehle R Roberts M Rodriguez D Sasaki N Schnetzer SR Scott LM Sinnis G Smith JD Sokolsky P Song C Springer RW 《Physical review letters》2008,100(10):101101
The High Resolution Fly's Eye (HiRes) experiment has observed the Greisen-Zatsepin-Kuzmin suppression (called the GZK cutoff) with a statistical significance of five standard deviations. HiRes' measurement of the flux of ultrahigh energy cosmic rays shows a sharp suppression at an energy of 6 x 10(19) eV, consistent with the expected cutoff energy. We observe the ankle of the cosmic-ray energy spectrum as well, at an energy of 4 x 10(18) eV. We describe the experiment, data collection, and analysis and estimate the systematic uncertainties. The results are presented and the calculation of the statistical significance of our observation is described. 相似文献
97.
98.
Competing first- and second-order reactions of transient molecular species (e.g., triplet states and free radicals) are a common occurrence in kinetic studies such as flash photolysis and pulse radiolysis. We have developed a method for analyzing the decay kinetics of any species (Y) whose disappearance is described by ?dY/dt = k1Y + k2Y2. The computer program (written in time-sharing BASIC) employs an iterative technique to obtain the least-squares estimates of the three parameters in the integrated rate equation. 相似文献
99.
100.