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1.
Electrochemical reduction of oxygen in the presence of an alpha-dimethylsilyl ester results in removal of the dimethylsilyl group. The reaction presumably proceeds by a mechanism involving electrochemically-generated superoxide ion.  相似文献   
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Since the data show that Bell inequalities are violated experimentally, we must conclude that any hidden variable theory (which correctly predicts experimental data ) will be non-local. But, to conclude that the experimental violations of Bell inequalities show quantum mechanics to be non-local is unjustified. Specifically, the key assumptions required to obtain a Bell inequality are ( 1 ) locality and (2) the assignment of meaningful ( non- negative) probabilities to seemingly physical correlations (Bell expresses these correlations via " hidden variables" ). Since the Bell inequality is violated by experiment, at least one of these assumptions is wrong. The widespread conclusion that locality must be relinquished is valid only if we retain the previously mentioned correlations ( "hidden variables" ). We will demonstrate that the latter are not physical observables - they are not elements of physical reality.  相似文献   
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The evolution of the venomous function of snakes and the diversification of the toxins has been of tremendous research interest and considerable debate. It has become recently evident that the evolution of the toxins in the advanced snakes (Colubroidea) predated the evolution of the advanced, front-fanged delivery mechanisms. Historically, the venoms of snakes lacking front-fanged venom-delivery systems (conventionally grouped into the paraphyletic family Colubridae) have been largely neglected. In this study we used liquid chromatography with mass spectrometry (LC/MS) to analyze a large number of venoms from a wide array of species representing the major advanced snake clades Atractaspididae, Colubrinae, Elapidae, Homalopsinae, Natricinae, Psammophiinae, Pseudoxyrhophiinae, Xenodontinae, and Viperidae. We also present the first sequences of toxins from Azemiops feae as well as additional toxin sequences from the Colubrinae. The large body of data on molecular masses and retention times thus assembled demonstrates a hitherto unsuspected diversity of toxins in all lineages, having implications ranging from clinical management of envenomings to venom evolution to the use of isolated toxins as leads for drug design and development. Although definitive assignment of a toxin to a protein family can only be done through demonstrated structural studies such as N-terminal sequencing, the molecular mass data complemented by LC retention information, presented here, do permit formulation of reasonable hypotheses concerning snake venom evolution and potential clinical effects to a degree not possible till now, and some hypotheses of this kind are proposed here. The data will also be useful in biodiscovery.  相似文献   
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