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61.
The authors follow up some previous work on the dynamics of pension funding by three notes. The first of these concerns contribution rates consisting of the normal cost plus a generalized amortization method for unfunded supplemental present value (actuarial accrued liability). The second note examines aggregate cost funding for active members when there exist consistent difference between the assumed and the actual rates of interest and of growth. The third note explores the operation of a variable annuity system in the context of our general model for pension funding dynamics. 相似文献
62.
The paper develops a theory of electron transfer with torsionally induced non-Condon (NC) effects. The starting point of the theory is a generalized spin-boson Hamiltonian, where an additional torsional oscillator bilinearly coupled to other bath modes causes a sinusoidal NC modulation. We derive closed form time dependent nonadiabatic rate expressions for both sudden and relaxed initial conditions, which are applicable for general spectral densities and energetic condition. Under the assumption that the torsional motion is not correlated with the polaronic shift of the bath, simple stationary limit rate expression is obtained. Model calculations of this rate expression illustrate the effects of torsional quantization and gating on the driving force and temperature dependences of the electron transfer rate. The classical limit of the rate expression consists of three Marcus-type terms, and is shown to agree very well with the exact numerical result. 相似文献
63.
Shirtcliffe NJ McHale G Newton MI Perry CC Roach P 《Chemical communications (Cambridge, England)》2005,(25):3135-3137
Switching between superhydrophobicity and superhydrophilicity in porous materials was predicted theoretically and demonstrated experimentally with the example of thermally induced contact angle change; tunability of this system was also demonstrated. 相似文献
64.
Iglesias-Juez A Martínez-Arias A Newton MA Fiddy SG Fernández-García M 《Chemical communications (Cambridge, England)》2005,(32):4092-4094
The redox behaviour of Pd-based TWCs is studied under dynamic, cycling conditions (e.g. lambda oscillations) on a 50 millisecond scale. Pd temporal response to gas inlet mixture changes is governed by metal-promoter interface properties. 相似文献
65.
P.A. Butler I.Y. Lee J.O. Newton Y. El-Masri M.M. Aleonard P. Colombani R.M. Diamond F.S. Stephens R.W. Lougheed E.K. Hulet 《Physics letters. [Part B]》1977,68(2):122-124
Excitation functions and angular distributions have been measured for the fission of 232Th, 238U, 244Pu and 248Cm induced by 86Kr and 136Xe ions at energies in the vicinity of the Coulomb barrier. No large differences as a function of either target or projectile were found. These results suggest that the main process occuring is not Coulomb fission. 相似文献
66.
H.Joseph Newton 《Journal of multivariate analysis》1978,8(2):317-323
Closed form matrix equations are given for the information matrix of the parameters of the vector mixed autoregressive moving average time series model. 相似文献
67.
68.
The main structural and electronic factors playing a role in intramolecular dissociative electron transfer of a simple donor-peptide-acceptor (D-peptide-A) model have been investigated by an integrated computational protocol based on the density functional theory, its time-dependent extension, and the polarizable continuum model. Our results allow us to elucidate the electronic states involved in the process and how they are perturbed by the orientation of the donor and the acceptor with respect to the peptide chain and by the presence of the solvent. We also report a semiquantitative estimation of the rate constant governing electron transfer obtained by a direct quantum mechanical evaluation of all the terms entering the kinetic expressions based on the Marcus theory and its extensions. 相似文献
69.
Strategies for examination of Alzheimer’s disease amyloid precursor protein isoforms 总被引:2,自引:0,他引:2
We describe a proteomics procedure using bioinformatics, immunoprecipitation, two-dimensional gel electrophoresis, Western blotting, in-gel digestion, LC–MS, MALDI–MS, and MS–MS for isolation and identification of amyloid precursor protein (APP) isoforms APP695, APP751, and APP770. Retinoic acid-induced Ntera 2 cell line, derived from a human teratocarcinoma cells, was the in-vitro source of APP. Initial isolation of whole APP was performed by immunoprecipitation, using AB10, a monoclonal antibody raised to amino acids 1–17 of the β-amyloid peptide sequence, which is present in all three alpha secretase-cleaved isoforms of interest. The next stage was separation of whole APP into its isoform components by two-dimensional gel electrophoresis. Because of low APP concentrations, detection by the usual staining methods, for example Sypro Ruby, able to detect low picomole concentrations, did not enable visualisation of the isoforms. Western analysis, however, enabled primary detection of APP, because of the inherent sensitivity of antibodies raised to specific isoform regions. This initial visualization acted as a template for excision of isoforms from 2D gels, which were then subjected to peptide mass mapping. Initial theoretical digestion of each isoform revealed the presence of specific peptides, which were then used as “tags” for isoform detection. 相似文献
70.
It is shown that the space of infinitesimal deformations of 2k-Einstein structures is finite dimensional on compact non-flat space forms. Moreover, spherical space forms are shown to be rigid in the sense that they are isolated in the corresponding moduli space. 相似文献