31,403 research outputs found
On vanishing sums of th roots of unity in finite fields
In an earlier work, the authors have determined all possible weights for
which there exists a vanishing sum of th roots
of unity in characteristic 0. In this paper, the same problem is
studied in finite fields of characteristic . For given and , results
are obtained on integers such that all integers are in the
``weight set'' . The main result in this paper guarantees,
under suitable conditions, the existence of solutions of
with all coordinates not equal to zero over a finite field
Elementary Proofs Of Two Theorems Involving Arguments Of Eigenvalues Of A Product Of Two Unitary Matrices
We give elementary proofs of two theorems concerning bounds on the maximum
argument of the eigenvalues of a product of two unitary matrices --- one by
Childs \emph{et al.} [J. Mod. Phys., \textbf{47}, 155 (2000)] and the other one
by Chau [arXiv:1006.3614]. Our proofs have the advantages that the necessary
and sufficient conditions for equalities are apparent and that they can be
readily generalized to the case of infinite-dimensional unitary operators.Comment: 8 pages in Revtex 4.1 preprint format, to appear in Journal of
Inequalities and Application
Hybrid biomedical intelligent systems
"Copyright © 2012 Maysam Abbod et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited."The purpose of this special issue is to promote research and developments of the best work in the field of hybrid intelligent systems for biomedical applications
Ligand-biased ensemble receptor docking (LigBEnD): a hybrid ligand/receptor structure-based approach.
Ligand docking to flexible protein molecules can be efficiently carried out through ensemble docking to multiple protein conformations, either from experimental X-ray structures or from in silico simulations. The success of ensemble docking often requires the careful selection of complementary protein conformations, through docking and scoring of known co-crystallized ligands. False positives, in which a ligand in a wrong pose achieves a better docking score than that of native pose, arise as additional protein conformations are added. In the current study, we developed a new ligand-biased ensemble receptor docking method and composite scoring function which combine the use of ligand-based atomic property field (APF) method with receptor structure-based docking. This method helps us to correctly dock 30 out of 36 ligands presented by the D3R docking challenge. For the six mis-docked ligands, the cognate receptor structures prove to be too different from the 40 available experimental Pocketome conformations used for docking and could be identified only by receptor sampling beyond experimentally explored conformational subspace
Origin of Discrepancies in Inelastic Electron Tunneling Spectra of Molecular Junctions
We report inelastic electron tunneling spectroscopy (IETS) of multilayer
molecular junctions with and without incorporated metal nano-particles. The
incorporation of metal nanoparticles into our devices leads to enhanced IET
intensity and a modified line-shape for some vibrational modes. The enhancement
and line-shape modification are both the result of a low lying hybrid metal
nanoparticle-molecule electronic level. These observations explain the apparent
discrepancy between earlier IETS measurements of alkane thiolate junctions by
Kushmerick \emph{et al.} [Nano Lett. \textbf{4}, 639 (2004)] and Wang \emph{et
al.} [Nano Lett. \textbf{4}, 643 (2004)].Comment: 4 pages, 4 figures accepted for publication in Physical Review
Letter
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