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841.
In S Orlov A García F Tikhov M Wright DS Lambert RM 《Chemical communications (Cambridge, England)》2006,(40):4236-4238
A reproducible and controllable method allows the synthesis of practical quantities of efficient, visible light active TiO(2)(N) photocatalysts in which the nitrogen content may be varied to achieve optimum performance. 相似文献
842.
843.
Delina Montes-Sánchez Jose Luis Ventura Irma Mitre Susana Frías Layla Michán Aurora Espejel-Nuñez Felipe Vadillo-Ortega Alejandro Zentella 《BMC chemical biology》2009,9(1):7-13
Background
Several common aspects of endothelial phenotype, such as the expression of cell adhesion molecules, are shared between metastasis and inflammation. Here, we analyzed VCAM-1 variants as biological markers of these two types of endothelial cell activation. With the combination of 2-DE and western blot techniques and the aid of tunicamycin, we analyzed N-glycosylation variants of VCAM-1 in primary human endothelial cells stimulated with either TNF or tumoral soluble factors (TSF's) derived from the human breast cancer cell line ZR75.30. 相似文献844.
Angel Felipe M. Teresa Ortu?o Gregorio Tirado 《4OR: A Quarterly Journal of Operations Research》2012,10(3):245-265
The joint optimization of routing and loading operations is crucial to fully optimize the overall planning process in logistics, and as a result routing problems with side constraints are becoming more and more important during the last years. This paper approaches the design of optimal routes for pickup and delivery operations considering in addition some capacity and loading constraints on the vehicles to be used. It is focused on exploiting new ideas to deal with real life situations in which the customers are not uniformly distributed on the pickup or delivery regions of the problem. An adapted and effective heuristic based on a Variable Neighborhood Search framework using improved neighborhood structures is proposed and discussed. The algorithm is applied to several new sets of instances with special structures to better represent real life situations, providing computational results to evaluate its performance. 相似文献
845.
Mostafa Bendahmane Felipe Wallison Chaves-Silva 《Comptes Rendus Mathematique》2012,350(11-12):587-590
This Note is devoted to the analysis of the null controllability of a nonlinear reaction–diffusion system, approximating a parabolic–elliptic system, modeling electrical activity in the heart. The uniform, with respect to the degenerating parameter, null controllability of the approximating system by a single control force acting on a subdomain is shown. The proof needs a precise estimate with respect to the degenerating parameter and it is done combining Carleman estimates and energy inequalities. 相似文献
846.
We perform, with the help of cloud computing resources, extensive Langevin simulations which provide compelling evidence in favor of a general Markovian framework for unbiased three-dimensional polymer translocation. Our statistical analysis consists of careful evaluations of (i) two-point correlation functions of the translocation coordinate and (ii) the empirical probabilities of complete polymer translocation (taken as a function of the initial number of monomers on a given side of the membrane). We find good agreement with predictions derived from the Markov chain approach recently addressed in the literature by the present authors. 相似文献
847.
848.
Yanet Fuentes‐Martínez Carolina Godoy‐Alcántar Felipe Medrano Alexander Dikiy 《Journal of Physical Organic Chemistry》2012,25(12):1395-1403
Imine formation in aqueous solution of kanamycin A with pyridoxal 5'‐phosphate and other aldehydes was studied by potentiometry, NMR spectroscopy and computational chemistry. It was found that imines are formed with yields near 100 % at pH 7 in equimolar reactant ratio. In order to identify the kanamycin amino groups involved in the reaction, a NMR spectroscopic study was conducted. The structures of possible imines formed between kanamycin and FURAN or PLP were optimized by molecular mechanics with the OPLS‐2005 force field. The 1H NMR spectra were calculated at the DFT‐GIAO B3LYP/6‐31G(d) level of theory for all structures and compared with the experimentally observed spectra. From these results a probable structure of the imines was proposed. The results obtained in this work show that kanamycin has the ability to form imine derivatives in high yields due to its anion recognition properties. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
849.
Bassam Felipe Mogharbel Marco Andr Cardoso Ana Carolina Irioda Priscila Elias Ferreira Stricker Robson Camilotti Slompo Julia Maurer Appel Nathalia Barth de Oliveira Maiara Carolina Perussolo Claudia Sayuri Saaki Nadia Nascimento da Rosa Dilcele Silva Moreira Dziedzic Christophe Travelet Sami Halila Redouane Borsali Katherine Athayde Teixeira de Carvalho 《Molecules (Basel, Switzerland)》2022,27(9)
Background: Parkinson’s disease (PD) is the second most common age-related neurodegenerative disorder. Levodopa (L-DOPA) remains the gold-standard drug available for treating PD. Curcumin has many pharmacological activities, including antioxidant, anti-inflammatory, antimicrobial, anti-amyloid, and antitumor properties. Copolymers composed of Poly (ethylene oxide) (PEO) and biodegradable polyesters such as Poly (ε-caprolactone) (PCL) can self-assemble into nanoparticles (NPs). This study describes the development of NH2–PEO–PCL diblock copolymer positively charged and modified by adding glutathione (GSH) on the outer surface, resulting in a synergistic delivery of L-DOPA curcumin that would be able to pass the blood–brain barrier. Methods: The NH2–PEO–PCL NPs suspensions were prepared by using a nanoprecipitation and solvent displacement method and coated with GSH. NPs were submitted to characterization assays. In order to ensure the bioavailability, Vero and PC12 cells were treated with various concentrations of the loaded and unloaded NPs to observe cytotoxicity. Results: NPs have successfully loaded L-DOPA and curcumin and were stable after freeze-drying, indicating advancing into in vitro toxicity testing. Vero and PC12 cells that were treated up to 72 h with various concentrations of L-DOPA and curcumin-loaded NP maintained high viability percentage, indicating that the NPs are biocompatible. Conclusions: NPs consisting of NH2–PEO–PCL were characterized as potential formulations for brain delivery of L-DOPA and curcumin. The results also indicate that the developed biodegradable nanomicelles that were blood compatible presented low cytotoxicity. 相似文献
850.
Mireya Santander-Nelli Bastin Boza Felipe Salas David Zambrano Luis Rosales Paulina Dreyse 《Molecules (Basel, Switzerland)》2022,27(9)
With an appropriate mixture of cyclometalating and ancillary ligands, based on simple structures (commercial or easily synthesized), it has been possible to design a family of eight new Ir(III) complexes (1A, 1B, 2B, 2C, 3B, 3C, 3D and 3E) useful as luminescent materials in LEC devices. These complexes involved the use of phenylpyridines or fluorophenylpyridines as cyclometalating ligands and bipyridine or phenanthroline-type structures as ancillary ligands. The emitting properties have been evaluated from a theoretical approach through Density Functional Theory and Time-Dependent Density Functional Theory calculations, determining geometric parameters, frontier orbital energies, absorption and emission energies, injection and transport parameters of holes and electrons, and parameters associated with the radiative and non-radiative decays. With these complexes it was possible to obtain a wide range of emission colours, from deep red to blue (701–440 nm). Considering all the calculated parameters between all the complexes, it was identified that 1B was the best red, 2B was the best green, and 3D was the best blue emitter. Thus, with the mixture of these complexes, a dual host–guest system with 3D-1B and an RGB (red–green–blue) system with 3D-2B-1B are proposed, to produce white LECs. 相似文献