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We study the finite-size effects associated with the appearance of a light, i.e. Goldstone, particle in the Kogut-Susskind lattice gauge theory. We analytically study the order parameter and the two-meson propagator in the strong coupling limit on a finite lattice. We give their explicit interpolations between the broken phase of the infinite-volume limit and the symmetric one of the finite system. We argue that the results obtained in the strong coupling limit are more general. 相似文献
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Andrew M. Raim Nagaraj K. Neerchal Jorge G. Morel 《Journal of computational and graphical statistics》2018,27(3):587-601
Finite mixture distributions arise in sampling a heterogeneous population. Data drawn from such a population will exhibit extra variability relative to any single subpopulation. Statistical models based on finite mixtures can assist in the analysis of categorical and count outcomes when standard generalized linear models (GLMs) cannot adequately express variability observed in the data. We propose an extension of GLMs where the response follows a finite mixture distribution and the regression of interest is linked to the mixture’s mean. This approach may be preferred over a finite mixture of regressions when the population mean is of interest; here, only one regression must be specified and interpreted in the analysis. A technical challenge is that the mixture’s mean is a composite parameter that does not appear explicitly in the density. The proposed model maintains its link to the regression through a certain random effects structure and is completely likelihood-based. We consider typical GLM cases where means are either real-valued, constrained to be positive, or constrained to be on the unit interval. The resulting model is applied to two example datasets through Bayesian analysis. Supporting the extra variation is seen to improve residual plots and produce widened prediction intervals reflecting the uncertainty. Supplementary materials for this article are available online. 相似文献
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Reactions of α‐thioxothioamides ( 1 ) with diisothiocyanates were carried out in the hope of generating the N,N′‐bis(1,3‐thiazoline‐2‐thiones) ( A ). Although that purpose could not be achieved, we succeeded in preparing the monocycloadducts 7 from the phenylene‐1,2‐diisothiocyanate ( 4 ). The benzimidazole derivatives 8 and 9 were also characterized and a mechanism was assumed to account for this intramolecular process. On the other hand, the regioselective synthesis of the N,N′‐biimidazole ( 13 ) containing the phenylene bridge was performed by the treatment of the 5‐aminothiazolium chloride ( 2 ) with the diisothiocyanate ( 4 ) in a basic medium. The mesoionic derivative 13 probably arises from the monoimidazolium‐4‐thiolate ( 12 ) which was shown to react with the salt 2 under similar conditions to give the primary cycloadduct 14 as an intermediate towards the bis(imidazolium) ( 13 ). © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:617–624, 2001 相似文献
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Interactions of Pt‐ttpy with G‐Quadruplexes Originating from Promoter Region of the c‐myc Gene Deciphered by NMR and Gel Electrophoresis Analysis 下载免费PDF全文