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951.
Early Membrane Responses to Magnetic Particles are Predictors of Particle Uptake in Neural Stem Cells
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![点击此处可从《Particle & Particle Systems Characterization》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Alinda R. Fernandes Christopher F. Adams David N. Furness Divya M. Chari 《Particle & Particle Systems Characterization》2015,32(6):661-667
Magnetic particles (MPs) offer several advantages for neural cell therapy, but limited particle uptake by neural cells is a barrier to translation. It is recently proved that tailoring particle physicochemical properties (by enhancing their iron content) dramatically improves uptake in neural stem cells (NSCs)—a major transplant population. High‐throughput screening of particles with varying physicochemical properties can therefore aid in identifying particles with optimal uptake features, but research is hampered by the lack of simple methodologies for studying neural cell membrane responses to nanoparticle platforms. A high‐resolution–high throughput method has been used to study early membrane responses of primary rodent NSCs to particles of variant magnetite loading, to attempt to correlate these responses with known particle internalization profiles. Membrane imaging is enhanced through sequential staining with osmium (O) and thiocarbohydrazide (T), a method termed OTOTO, combined with field‐emission scanning electron microscopy (FESEM). A five‐point classification system was used to systematically evaluate early MP‐induced membrane responses to particles possessing distinct physicochemical properties. Significantly different profiles of membrane activation were noted that correlate with particle uptake profiles. It is suggested that our method can serve as a valuable predictor of particle internalization in neural cells for diverse particle platforms. 相似文献
952.
Renata S. Amais Stephen E. Long Joaquim A. Nóbrega Steven J. Christopher 《Analytica chimica acta》2014
A method is described for quantification of sulfur at low concentrations on the order of mg kg−1 in biodiesel and diesel fuels using isotope dilution and sector field inductively coupled plasma mass spectrometry (ID-SF-ICP-MS). Closed vessel microwave-assisted digestion was employed using a diluted nitric acid and hydrogen peroxide decomposition medium to reduce sample dilution volumes. Medium resolution mode was employed to eliminate isobaric interferences at 32S and 34S related to polyatomic phosphorus and oxygen species, and sulfur hydride species. The method outlined yielded respective limits of detection (LOD) and limits of quantification (LOQ) of 0.7 mg kg−1 S and 2.5 mg kg−1 S (in the sample). The LOD was constrained by instrument background counts at 32S but was sufficient to facilitate value assignment of total S mass fraction in NIST SRM 2723b Sulfur in Diesel Fuel Oil at 9.06 ± 0.13 mg kg−1. No statistically significant difference at a 95% confidence level was observed between the measured and certified values for certified reference materials NIST SRM 2773 B100 Biodiesel (Animal-Based), CENAM DRM 272b and NIST SRM 2723a Sulfur in Diesel Fuel Oil, validating method accuracy. 相似文献
953.
James D. Oliver Adam A. Rosser Christopher M. Fellows Yohann Guillaneuf Jean-Louis Clement Marianne Gaborieau Patrice Castignolles 《Analytica chimica acta》2014
Direct UV detection of carbohydrates in free solution capillary electrophoresis at 270 nm is made possible by a photo-oxidation reaction. Glucose, rhamnose and xylose were shown to have unique UV absorption spectra hypothesizing different UV absorbing intermediates for their respective photo-oxidation. NMR spectroscopy of the photo-oxidation end products proved they consisted of carboxylates and not malondialdehyde as previously theorized and that oxygen thus plays a key role in the photo-oxidation pathway. Adding the photo-initiator Irgacure® 2959 in the background electrolyte increased sensitivity by 40% at an optimum concentration of 1 × 10−4 mM and 1 × 10−8 mM for conventional 50 μm i.d. capillaries and for the corresponding extended light path capillaries, respectively. 相似文献
954.
Arylspiroborates Derived from 4‐tert‐Butylcatechol and 3,5‐Di‐tert‐butylcatechol and Their Antimicrobial Activities
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![点击此处可从《Journal of heterocyclic chemistry》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Michael I. Webb Nathan R. Halcovitch Eric G. Bowes Graham M. Lee Michael J. Geier Christopher M. Vogels Taryn O'Neill Haoxin Li Andrew Flewelling Andreas Decken Christopher A. Gray Stephen A. Westcott 《Journal of heterocyclic chemistry》2014,51(1):157-161
A family of arylspiroborates has been prepared by the addition of either 4‐tert‐butylcatechol or 3,5‐di‐tert‐butylcatechol to boric acid and an alkali metal hydroxide. All compounds were characterized fully using multinuclear NMR spectroscopy and by elemental analyses. A single crystal X‐ray diffraction was carried out on potassium (bis‐(3,5‐di‐tertbutyl[1,2‐benzenediolato(2‐)‐O,O′]borate)) ( 8 ). All compounds displayed appreciable anti‐microbial activities. 相似文献
955.
Sebastian Reicherts Sebastian Blume Christopher Reichert Dr.-Ing. Dr. h.c. Dieter Schramm 《PAMM》2016,16(1):859-860
Uncertainties in the kinematic parameters like the pulley positions take a major influence onto the force capability of a cable-driven parallel robot. For that purpose this paper describes a calibration method to estimate exactly the underlying kinematic parameters. As the kinematic is influenced by a variety of different parameter, the calibration can be very complex and time consuming. In this approach, a sensitivity analysis of a cable-driven parallel robot is presented to simplify and enhance the calibration. The results are discussed and the further steps are introduced. (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
956.
Radu?Ioan?Bo?Email author Ern??Robert?Csetnek André?Heinrich Christopher?Hendrich 《Mathematical Programming》2015,150(2):251-279
We present two modified versions of the primal-dual splitting algorithm relying on forward–backward splitting proposed in V\(\tilde{\mathrm{u}}\) (Adv Comput Math 38(3):667–681, 2013) for solving monotone inclusion problems. Under strong monotonicity assumptions for some of the operators involved we obtain for the sequences of iterates that approach the solution orders of convergence of \(\mathcal{{O}}(\frac{1}{n})\) and \(\mathcal{{O}}(\omega ^n)\), for \(\omega \in (0,1)\), respectively. The investigated primal-dual algorithms are fully decomposable, in the sense that the operators are processed individually at each iteration. We also discuss the modified algorithms in the context of convex optimization problems and present numerical experiments in image processing and pattern recognition in cluster analysis. 相似文献
957.
A concise stereoselective route to the dysiherbaine tetrahydropyran core was achieved in nine steps and 39% overall yield. Donohoe’s improved tethered aminohydroxylation conditions were employed to concurrently install the amino and alcohol groups and construct the tetrahydropyran ring, which features four contiguous cis-stereocenters. 相似文献
958.
Pradeep P. KapadiaJohn C. Widen Mackenzie A. MagnusDale C. Swenson F. Christopher Pigge 《Tetrahedron letters》2011,52(19):2519-2522
Two tetrapyridyl-substituted tetraphenylethylenes have been prepared via Suzuki coupling between tetrabromo tetraphenylethylene and 3- or 4-pyridine boronic acid. Both compounds exhibit aggregation-induced emission as determined by solid state fluorescence spectroscopy and solution phase fluorescence measurements performed in aqueous/organic solvent mixtures. Solution phase fluorescence was also found to be switchable as a function of pH. 3-Pyridyl-substituted tetraphenylethylene has been structurally characterized by X-ray crystallography. 相似文献
959.
The powerful self-assembly features of DNA make it a unique template to finely organize and control matter on the nanometre scale. While DNA alone offers a high degree of fidelity in its self-assembly, a new area of research termed 'supramolecular DNA assembly' has recently emerged. This field combines DNA building blocks with synthetic organic, inorganic and polymeric structures. It thus brings together the toolbox of supramolecular chemistry with the predictable and programmable nature of DNA. The result of this molecular partnership is a variety of hybrid architectures, that expand DNA assembly beyond the boundaries of Watson-Crick base pairing into new structural and functional properties. In this tutorial review we outline this emerging field of study, and describe recent research aiming to synergistically combine the properties inherent to DNA with those of a number of supramolecular scaffolds. This ultimately creates structures with numerous potential applications in materials science, catalysis and medicine. 相似文献
960.
Bates CM Strahan JR Santos LJ Mueller BK Bamgbade BO Lee JA Katzenstein JM Ellison CJ Willson CG 《Langmuir : the ACS journal of surfaces and colloids》2011,27(5):2000-2006
The orientation of cylinder-forming poly(styrene-block-methyl methacrylate) [P(S-b-MMA)] was investigated on two sets of polymeric surface treatments: 10 para-substituted polystyrene derivatives with <10 mol % poly(4-vinylbenzyl azide) and a series of poly(styrene-random-4-vinylbenzyl azide) [P(S-r-VBzAz)] copolymers with 5-100 mol % poly(4-vinylbenzyl azide). The copolymers were spin-coated to form thin films and then cross-linked by heating. The resulting films exhibited a range of surface tensions from 21 to 45 dyn/cm. Perpendicular orientation of P(S-b-MMA) cylinders was achieved with poly(p-bromostyrene) and all the [P(S-r-VBzAz)] copolymer surface treatments, most notably the homopolymer of poly(4-vinylbenzyl azide). Films made from these simple copolymers are as effective as random terpolymer alignment layers commonly made from both block monomers and a cross-linkable monomer. 相似文献