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Keith Jonathan M. Kroese Dirk P. Bryant Darryn 《Methodology and Computing in Applied Probability》2004,6(1):29-53
A recent development of the Markov chain Monte Carlo (MCMC) technique is the emergence of MCMC samplers that allow transitions between different models. Such samplers make possible a range of computational tasks involving models, including model selection, model evaluation, model averaging and hypothesis testing. An example of this type of sampler is the reversible jump MCMC sampler, which is a generalization of the Metropolis–Hastings algorithm. Here, we present a new MCMC sampler of this type. The new sampler is a generalization of the Gibbs sampler, but somewhat surprisingly, it also turns out to encompass as particular cases all of the well-known MCMC samplers, including those of Metropolis, Barker, and Hastings. Moreover, the new sampler generalizes the reversible jump MCMC. It therefore appears to be a very general framework for MCMC sampling. This paper describes the new sampler and illustrates its use in three applications in Computational Biology, specifically determination of consensus sequences, phylogenetic inference and delineation of isochores via multiple change-point analysis. 相似文献
3.
KL Britton HF Rogers Y Asano T Dairi Y Kato TJ Stillman DW Rice 《Acta crystallographica. Section D, Biological crystallography》1998,53(4):124-126
The novel NAD+-linked opine dehydrogenase from a soil isolate Arthrobacter sp. strain 1C belongs to an enzyme superfamily whose members exhibit quite diverse substrate specificites. Crystals of this opine dehydrogenase, obtained in the presence or absence of co-factor and substrates, have been shown to diffract to beyond 1.8 ? resolution. X-ray precession photographs have established that the crystals belong to space group P21212, with cell parameters a = 104.9, b = 80.0, c = 45.5 ? and a single subunit in the asymmetric unit. The elucidation of the three-dimensional structure of this enzyme will provide a structural framework for this novel class of dehydrogenases to enable a comparison to be made with other enzyme families and also as the basis for mutagenesis experiments directed towards the production of natural and synthetic opine-type compounds containing two chiral centres. 相似文献
4.
We present an asymptotic analysis of the boundary-generated, small-amplitude, high-frequency waves in a one-dimensional, semi-infinite, viscoelastic solid characterized by a single-integral constitutive functional. The equations governing the wave motion constitute a 2×2 system of hyperbolic Volterra integrodifferential equations. The method of analysis is based on a single-wave expansion of nonlinear geometric optics. 相似文献
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For all oddv 3 the complete graph onvK
v
vertices can be decomposed intov – 2 edge disjoint cycles whose lengths are 3, 3, 4, 5,...,v – 1. Also, for all oddv 7,K
v
can be decomposed intov – 3 edge disjoint cycles whose lengths are 3, 4,...,v – 4,v – 2,v – 1,v.
Research supported by Australian Research Council grant A49130102 相似文献
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M. S. Bryant J. O. Lay M. P. Chiarelli 《Journal of the American Society for Mass Spectrometry》1992,3(4):360-371
An analytical strategy using fast atom bombardment (FAB) ionization and tandem mass spectrometry has been developed to determine the molecular weight and major fragment ions, and to provide limited structural characterization of low picomole levels of carcinogen-nucleoside adducts. This strategy consists of three main components: (1) the sensitivity for analysis by FAB combined with mass spectrometry is increased via chemical derivatization; (2) the nucleoside adducts are selectively detected by using constant neutral loss scans; and (3) structurally characteristic fragments are obtained by using daughter ion scans. Trimethylsilyl derivatized arylamine-nucleoside adducts have been detected at levels as low as a few picomoles by using this approach. After experimental determination of the mass of the BH 2 + fragment ion, daughter ion spectra have been used to probe the structure specificity associated with collision-activated decomposition of this fragment. With model C-8 substituted arylamine adducts [N-(deoxyguanosin-8-yl)-4-aminobiphenyl, N-(deoxyadenosin--yl)-4-aminobiphenyl, and N-(deoxyguanosin-8-yl)-2-aminofluorene], nucleoside-specific and carcinogen-specific fragmentation have been observed in daughter ion spectra. 相似文献
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Darryn E. Bryant 《Designs, Codes and Cryptography》1992,2(2):159-168
For m = 6 and for all odd composite integers m, as well as for all even integers m 10 that satisfy certain conditions, 2-perfect m-cycle systems are constructed whose quasigroups have a homomorphism onto quasigroups which do not correspond to a 2-perfect m-cycle systems. Thus it is shown that for these values of m the class of quasigroups arising from all 2-perfect m-cycle systems does not form a variety. 相似文献