4,110 research outputs found
Infinitesimal Progress : Rethinking Bergsonian Modalities of Time in William Faulkner\u27s Novels, 1929-1932
William Faulknerâs depictions of the past are as ornate as they are inescapable. His characters cannot escape the perpetual imposition of the past upon the present; entire lineages fall victim to the flaws of their fathers, history is as cyclical as the movements of a wagon along a dusty Mississippi road. This thesis explains the Bergsonian mechanics of duration present in The Sound and the Fury, As I Lay Dying, and Light in August and reevaluates the fatalistic implications Faulknerâs macabre characters face recursively in and through time. Much of the critical exploration of time in Faulknerâs fiction is outmoded and does not correspond with current modes of analysis, particularly race and gender studies. However, a critical reevaluation of Faulknerâs fatalistic depictions of time offers new studies a different undertaking. This thesis explores the implications of reuniting Bergsonism and three of Faulknerâs novels, concentrating on the significant implications wagons and wagon wheels bear on a paradoxically static but perpetually moving time. Through this reading, this thesis offers a nuanced account of what temporal modalities in Faulkner might amount to in this century
H2 molecule in strong magnetic fields
The Pauli-Hamiltonian of a molecule with fixed nuclei in a strong constant
magnetic field is asymptotic, in norm-resolvent sense, to an effective
Hamiltonian which has the form of a multi-particle Schr\"odinger operator with
interactions given by one-dimensional \delta-potentials. We study this
effective Hamiltonian in the case of the H2 -molecule and establish existence
of the ground state. We also show that the inter-nuclear equilibrium distance
tends to 0 as the field-strength tends to infinity
Enantioselective palladium-catalyzed allylic alkylation reactions in the synthesis of Aspidosperma and structurally related monoterpene indole alkaloids
Enantioselective Pd-catalyzed allylic alkylations of prochiral enolates represent a powerful tool for the construction of all-carbon quaternary stereocenters. This review describes the emergence of such reactions as strategic linchpins that enable efficient, stereocontrolled syntheses of Aspidosperma and related monoterpene indole alkaloids
Enantioselective palladium-catalyzed allylic alkylation reactions in the synthesis of Aspidosperma and structurally related monoterpene indole alkaloids
Enantioselective Pd-catalyzed allylic alkylations of prochiral enolates represent a powerful tool for the construction of all-carbon quaternary stereocenters. This review describes the emergence of such reactions as strategic linchpins that enable efficient, stereocontrolled syntheses of Aspidosperma and related monoterpene indole alkaloids
The Value of Comparative Animal Research : Kroghâs Principle Facilitates Scientific Discoveries
There are no conflicts of interest to declare. This paper developed from the 2016 Early Career Impact Award from the Federation of Associations in Behavioral & Brain Sciences to TJS. TJS has received funding from The Leverhulme Trust. FJPE is in receipt of funding from the BBSRC (BB/M001555/1). The National Institutes of Health has funded RDF (NS 034950, NS093277, NIMH 087930), AGO (HD079573, IOS-1354760) and AMK (HD081959). BAA is an Arnold O. Beckman postdoctoral fellow.Peer reviewedPostprin
The Total Synthesis of (â)-Scabrolide A
The first total synthesis of the norcembranoid diterpenoid scabrolide A is disclosed. The route begins with the synthesis of two chiral pool-derived fragments, which undergo a convergent coupling to expediently introduce all 19 carbon atoms of the natural product. An intramolecular DielsâAlder reaction and an enoneâolefin cycloaddition/fragmentation sequence are then employed to construct the fused [5â6â7] linear carbocyclic core of the molecule and complete the total synthesis
Angular Power Spectrum Estimation of Cosmic Ray Anisotropies with Full or Partial Sky Coverage
We study the angular power spectrum estimate in order to search for large
scale anisotropies in the arrival directions distribution of the highest-energy
cosmic rays. We show that this estimate can be performed even in the case of
partial sky coverage and validated over the full sky under the assumption that
the observed fluctuations are statistically spatial stationary. If this
hypothesis - which can be tested directly on the data - is not satisfied, it
would prove, of course, that the cosmic ray sky is non isotropic but also that
the power spectrum is not an appropriate tool to represent its anisotropies,
whatever the sky coverage available. We apply the method to simulations of the
Pierre Auger Observatory, reconstructing an input power spectrum with the
Southern site only and with both Northern and Southern ones. Finally, we show
the improvement that a full-sky observatory brings to test an isotropic
distribution, and we discuss the sensitivity of the Pierre Auger Observatory to
large scale anisotropies.Comment: 16 pages, 6 figures, version accepted for publication by JCA
Enantioselective Catalysis Coupled with Stereodivergent Cyclization Strategies Enables Rapid Syntheses of (+)-Limaspermidine and (+)-Kopsihainanine A
Enantioselective Pd-catalyzed allylic alkylations of dihydropyrido[1,2-a]indolone (DHPI) substrates were used to construct the C20-quaternary stereocenters of multiple monoterpene indole alkaloids. Stereodivergent PictetâSpengler and BischlerâNapieralski cyclization/reduction cascades furnish the cis- and trans-fused azadecalin subunits present in Aspidosperma and Kopsia alkaloids, respectively, enâ
route to highly efficient syntheses of (+)-limaspermidine and (+)-kopsihainanineâ
A
Enantioselective Pd-Catalyzed Allylic Alkylation Reactions of Dihydropyrido[1,2-a]indolone Substrates: Efficient Syntheses of (â)-Goniomitine, (+)-Aspidospermidine, and (â)-Quebrachamine
The successful application of dihydropyrido[1,2-a]indolone (DHPI) substrates in Pd-catalyzed asymmetric allylic alkylation chemistry facilitates rapid access to multiple alkaloid frameworks in an enantioselective fashion. Strategic bromination at the indole C3 position greatly improved the allylic alkylation chemistry and enabled a highly efficient Negishi cross-coupling downstream. The first catalytic enantioselective total synthesis of (â)-goniomitine, along with divergent formal syntheses of (+)-aspidospermidine and (â)-quebrachamine, are reported herein
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