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51.
Tho Duc Khanh Nguyen Stefania Rabasco Alicia A. Lork Andre Du Toit Prof. Andrew G. Ewing 《Angewandte Chemie (International ed. in English)》2023,62(28):e202304098
We used correlative transmission electron microscopy (TEM) and nanoscale secondary ion mass spectrometry (NanoSIMS) imaging to quantify the contents of subvesicular compartments, and to measure the partial release fraction of 13C-dopamine in cellular nanovesicles as a function of size. Three modes of exocytosis comprise full release, kiss-and-run, and partial release. The latter has been subject to scientific debate, despite a growing amount of supporting literature. We tailored culturing procedures to alter vesicle size and definitively show no size correlation with the fraction of partial release. In NanoSIMS images, vesicle content was indicated by the presence of isotopic dopamine, while vesicles which underwent partial release were identified by the presence of an 127I-labelled drug, to which they were exposed during exocytosis allowing entry into the open vesicle prior to its closing again. Demonstration of similar partial release fractions indicates that this mode of exocytosis is predominant across a wide range of vesicle sizes. 相似文献
52.
Richard Ewing Raytcho Lazarov Yanping Lin 《Numerical Methods for Partial Differential Equations》2000,16(3):285-311
In this article, we study finite volume element approximations for two‐dimensional parabolic integro‐differential equations, arising in the modeling of nonlocal reactive flows in porous media. These types of flows are also called NonFickian flows and exhibit mixing length growth. For simplicity, we consider only linear finite volume element methods, although higher‐order volume elements can be considered as well under this framework. It is proved that the finite volume element approximations derived are convergent with optimal order in H1‐ and L2‐norm and are superconvergent in a discrete H1‐norm. By examining the relationship between finite volume element and finite element approximations, we prove convergence in L∞‐ and W1,∞‐norms. These results are also new for finite volume element methods for elliptic and parabolic equations. © 2000 John Wiley & Sons, Inc. Numer Methods Partial Differential Eq 16: 285–311, 2000 相似文献
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David F. Ewing Christophe Len Grahame Mackenzie Gino Ronco Pierre Villa 《Tetrahedron: Asymmetry》2000,11(24)
1,2-O-Isopropylidene-α-
-xylofuranose has been used to protect one aldehyde group of o-phthalaldehyde. This chiral protecting group acts as a resolving agent and this leads to separable diastereoisomers when a new stereogenic centre is created by the conversion of the second aldehyde group to a benzyloxyhydroxyethyl chain. These separated diastereoisomers were cyclised to 1,3-dihydrobenzo[c]furans with retention of chiral integrity at the C3 site thus allowing further elaboration to enantiomerically pure nucleoside analogues. 相似文献
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Treatment of a primary t-butyl carbamate (Boc) group with excess sodium t-butoxide in slightly wet tetrahydrofuran or 2-methyltetrahydrofuran provides the corresponding primary amine in excellent yield. We believe the reaction proceeds through an isocyanate intermediate. 相似文献
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The preparation and characterization of new tetrahalodimolybdenum(II) complexes with alkyl-substituted pyridines is described. IR and visible data are used to infer structural information with respect to previously prepared complexes of this type. 相似文献
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Parent beliefs about roles of education, teachers, computers, and innovative mathematics instruction were examined through factor analysis. Strong relationships between parent beliefs regarding teacher and computer roles were found. The beliefs of parents about the similar roles of teachers and computers in education may impact the implementation of innovations in mathematics education and the uses of computers in education. Reciprocally, the ways computers are implemented in education may impact the beliefs parents have about the purposes of education. 相似文献