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151.
The MELANIE project: from a biopsy to automatic protein map interpretation by computer. 总被引:3,自引:0,他引:3
R D Appel D F Hochstrasser M Funk J R Vargas C Pellegrini A F Muller J R Scherrer 《Electrophoresis》1991,12(10):722-735
The goals of the MELANIE project are to determine if disease-associated patterns can be detected in high resolution two-dimensional polyacrylamide gel electrophoresis (HR 2D-PAGE) images and if a diagnosis can be established automatically by computer. The ELSIE/MELANIE system is a set of computer programs which automatically detect, quantify, and compare protein spots shown on HR 2D-PAGE images. Classification programs help the physician to find disease-associated patterns from a given set of two-dimensional gel electrophoresis images and to form diagnostic rules. Prototype expert systems that use these rules to establish a diagnosis from new HR 2D-PAGE images have been developed. They successfully diagnosed cirrhosis of the liver and were able to distinguish a variety of cancer types from biopsies known to be cancerous. 相似文献
152.
Braga AL Lüdtke DS Vargas F Paixão MW 《Chemical communications (Cambridge, England)》2005,(19):2512-2514
The catalytic enantioselective arylation of several aldehydes using boronic acids as the source of transferable aryl groups is described; the reaction is found to proceed in excellent yields and high enantioselectivities (up to 97% ee) in the presence of a chiral amino alcohol. 相似文献
153.
ter Steege DH Smits M de Lange CA Westwood NP Peel JB Visscher L 《Faraday discussions》2000,(115):259-69; discussion 303-30
A (2 + 1) one-colour resonance-enhanced multiphoton ionisation study is carried out on the C 2 sigma- state of the ClO radical in the one-photon energy range 29,500-31,250 cm-1. The ClO radical is produced by one-photon photolysis of ClO2 employing 359.2 nm photons derived from a separate laser. In this way a significant concentration of vibrationally excited ClO in its spin-orbit split X 2 pi omega (omega = 3/2 or 1/2) electronic ground state is produced. In addition to mass-resolved excitation spectra, kinetic-energy resolved photoelectron spectra for the X 3 sigma-(v+)<--C 2 sigma-(v' = 3-5) transitions are measured. These transitions are not completely Frank-Condon diagonal, and indicate a decrease in bond length on removal of the Rydberg electron from the C 2 sigma- state. In addition to an unambiguous assignment of the C 2 sigma- state, valuable information is obtained on the degree of vibrational excitation with which the nascent ClO radical is formed in the photolysis of ClO2. Analysis of the photoelectron spectra is supported by Franck-Condon calculations based on potential energy curves either from experimental spectroscopic parameters, or obtained by theoretical ab initio methods. 相似文献
154.
José G. Vargas 《Foundations of Physics》1986,16(12):1231-1261
The revised Robertson's test theory of special relativity (SR) has been constructed upon a family of sets of passive coordinate transformations in flat space-time [J. G. Vargas and D. G. Torr,Found. Phys., 16, 1089 (1986)]. In the same paper, it has also been shown that the boosts depend in general on the velocities of the two frames involved and not only on their relative velocity. The only exception to this is SR, if one has previously used an appropriate constraint to remove the other relativities—like Galilean relativity—from the family.In this paper we look at these coordinate transformations in the only way there is to do so, namely as transformations in a seven-dimensional Cartan Space (Cartan first considered this in his dealings with Newtonian kinematics). In this space, the boosts only depend on the relative velocity of the frames. The passive coordinate transformations in each set are shown to have a nonlinear group structure isomorphic to that of the Poincaré group.The existence of a preferred frame, except in SR, makes the active transformations inequivalent to the passive ones. It is shown that the composite active-passive transformations act on a ten-dimensional space and that each member set of the family also has a group structure. As a result, one ends up with a family of mutually isomorphic 9-parameter (homogeneous) supergroups and a family of mutually isomorphic (9 + 4)-parameter (inhomogeneous) supergroups. The presence of extra parameters could be looked upon as internal degrees of freedom, which are, however, an offshoot of the Robertson space-time.Part of this work was done while the author was at Departmento de Física, Universidad del Zulia, Maracaibo, Venezuela, and at Department of Physics, Utah State University, Logan, Utah. 相似文献
155.
R. Figueroa D. Caro A. Vargas A. Gordon V. Poblete 《Journal of Radioanalytical and Nuclear Chemistry》1995,198(2):311-316
A methodology of comparison is presented as a way to determine the origin of ceramic fragments proceeding from clays and archaeological sites of the 9th Region of Chile, analyzed through X-ray fluorescence (XRF) spectroscopy. Net areas of peak of sample spectra, are analysed using the graphic polygonal method, developed previously.1,2 Criterions of comparison have been defined as a way to determine similarity degrees and proceeding places. Polygonal representations used are triangles, squares, pentagons and hexagons; the similarity grading among samples is defined. Results are compared with clay samples and sand removing effects on fragments are also defined. 相似文献
156.
Summary The synthesis, characterization and electrochemical behaviour of a new series of copper(II) complexes derivated from substituted anilines and bromosalicylaldehydes have been studied.The complexes show a square-plane stereochemistry in solution. The reduction potentials depend on the substitutents in the salicylaldehydes and on the precursor anilines. The evaluation of kinetic parameters show a single stage one-electron transfer. 相似文献
157.
158.
159.
Kieran Griffiths Dr. Christopher W. D. Gallop Dr. Alaa Abdul‐Sada Dr. Alfredo Vargas Dr. Oscar Navarro Dr. George E. Kostakis 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(17):6358-6361
Three isoskeletal tetranuclear coordination clusters with general formula [MII2DyIII2L4(EtOH)6](ClO4)2?2 EtOH, (M=Co, 1 ; M=Ni, 2 ) and [NiII2DyIII2L4Cl2(CH3CN)2]?2 CH3CN ( 3 ), have been synthesized and characterized. These air‐stable compounds, and in particular 3 , display efficient homogeneous catalytic behavior in the room‐temperature synthesis of trans‐4,5‐diaminocyclopent‐2‐enones from 2‐furaldehyde and primary or secondary amines under a non‐inert atmosphere. 相似文献
160.
Cover Picture: Platinum trans‐Bis(borirene) Complexes Displaying Coplanarity and Communication Across a Platinum Metal Center (Chem. Eur. J. 6/2015)
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