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111.
Riccardo Rosso André M. Sonnet Epifanio G. Virga 《Continuum Mechanics and Thermodynamics》2002,14(1):127-136
kinks created in a biological membrane by the interaction with a movable bead. We arrive at the evolution equations for both the
bead and the membrane, whence we conclude that the force exerted on the bead by a fixed membrane points in the direction along
which the curvature of the membrane is more concentrated. This is the first step towards understanding the basic mechanism
behind the dynamics of protein aggregation which takes place on biological membranes.
Received November 6, 2001 / Published online February 4, 2002 相似文献
112.
Donato Bini Christian Cherubini Marco de Mattia Robert T. Jantzen 《General Relativity and Gravitation》2003,35(12):2249-2260
Accelerated circular orbits in the equatorial plane of the Taub-NUT spacetime are analyzed to investigate the effects of its gravitomagnetic monopole source. The effect of a small gravitomagnetic monopole on these orbits is compared to the corresponding orbits pushed slightly off the equatorial plane in the absence of the monopole. 相似文献
113.
Giacomo?Saielli Riccardo?Bini Alessandro?BagnoEmail author 《Theoretical chemistry accounts》2012,131(3):1140
Fluorine-19 NMR chemical shifts have been calculated for a wide variety of fluorine-containing inorganic and organic molecules
by relativistic DFT methods. The agreement with experimental values, spanning the whole range from ClF to FOOF, is satisfactory
but somewhat less accurate than for comparable light nuclei. 19F shifts in uranium chlorofluorides have been analyzed in detail, and the poor agreement with experiment is partly rationalized. 相似文献
114.
Riccardo Flamini Mirko De Rosso Annarita Panighel Antonio Dalla Vedova Fabiola De Marchi Luigi Bavaresco 《Journal of mass spectrometry : JMS》2014,49(12):1214-1222
A ‘suspect screening analysis’ method for grape metabolomics by ultra‐high performance‐liquid chromatography (UHPLC) and high‐resolution quadrupole‐time of flight (QTOF) mass spectrometry was recently developed. This method was applied to study grape monoterpene glycosides, the main grape aroma precursors. Since standard compounds were not available, they were tentatively identified by overlapping various analytical approaches, in agreement with the indications recommended in mass spectrometry (MS)‐based metabolomics. Accurate mass and isotopic pattern, MS/MS fragmentation, correlation between fragments observed and putative structures and between liquid chromatography coupled with mass spectrometry (LC/MS) and gas chromatography/mass spectrometry signals were studied. Seventeen monoterpene glycosides were identified without performing the hydrolytic artifacts commonly used to study these compounds which may affect sample profile. This is the first time that a detailed study of these aroma precursors has been carried out by direct LC/MS analysis. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
115.
Wolfgang Bermel Dr. Ivano Bertini Prof. Isabella C. Felli Prof. Riccardo Peruzzini Roberta Pierattelli Prof. 《Chemphyschem》2010,11(3):689-695
Provided that 13C‐detected NMR experiments are either preferable or complementary to 1H detection, we report here tools to determine Cα? C′, C′? N, and Cα? Hα residual dipolar couplings on the basis of the CON experiment. The coupling constants determined on ubiquitin are consistent with the subset measured with the 1H‐detected HNCO sequences. Since the utilization of residual dipolar couplings may depend on the mobility of the involved nuclei, we also provide tools to measure longitudinal and transverse relaxation rates of N and C′. This new set of experiments is a further development of a whole strategy based on 13C direct‐detection NMR spectroscopy for the study of biological macromolecules. 相似文献
116.
Guglielmo Monaco 《Journal of mathematical chemistry》2011,49(8):1544-1557
A novel exact derivation for the kinetic constant of a bimolecular reaction according to three well-known models of collision
theory is reported. The use of probability density functions, with the introduction of a novel geometry to study the collision
process, allows simplifying the derivation to such an extent, that, for a proper statistical background, it is is possible
to recover the line-of-centers and the angular dependent line-of-centers models in no more than a couple of lectures. Although
the derivation is introduced to recover the temperature-dependent kinetic constant, it is shown that the energy-dependent
reactive cross section can be recovered as well. A possible confusion in the interpretation of the pre-exponential factor
is commented. 相似文献
117.
Riccardo Fazio 《Journal of Computational and Applied Mathematics》1994,50(1-3):299-303
Within group invariance theory we consider a constructive approach in order to define numerical transformation methods. These are initial-value methods for the solution of boundary value problems governed by ordinary differential equations. Here we consider the class of free boundary value problems governed by the most general second-order equation in normal form. For this class of problems the main theorem is concerned with the definition of an iterative transformation method. The definition of a noniterative method, applicable to a subclass of the original class of problems, follows as a corollary. Therefore, the proposed constructive approach allows us to establish a unifying framework for noniterative and iterative transformation methods. 相似文献
118.
We study the dynamics of a noisy network of spiking neurons with spike-frequency adaptation (SFA), using a mean-field approach, in terms of a two-dimensional Fokker-Planck equation for the membrane potential of the neurons and the calcium concentration gating SFA. The long time scales of SFA allow us to use an adiabatic approximation and to describe the network as an effective nonlinear two-dimensional system. The phase diagram is computed for varying levels of SFA and synaptic coupling. Two different population-bursting regimes emerge, depending on the level of SFA in networks with noisy emission rate, due to the finite number of neurons. 相似文献
119.
120.