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Given an expansive action α of ?2 by automorphisms of a compact connected metrizable abelian groupX, we show how the entropy of the action may be decomposed into local contributions, 1 $$h(\alpha ) = \sum\limits_{p \leqslant \infty } {h_p^{(a,b)} } (\alpha )$$ in which the summandh p (a,b) (α) represents thep-adic entropy due to arithmetic or geometric hyperbolicity in the direction (a, b). We recognize thep-adic contribution as an integral over thep-adic unit circle, in analogy with the global counterpart. As (a, b) changes, the decomposition (1) changes only when the line through (a, b) passes through one of a finite collection of critical directions, which are explicitly identified. 相似文献
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Summary We prove that every mixing
d
by automorphisms of a compact, connected, abelian group is mixing of all orders.Oblatum 5-II-1992The second author gratefully acknowledges support from NSF grant DMS-91-03056 at the Ohio State University 相似文献
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Mössbauer spectra and X-ray diffraction data have been recorded for compounds in the solid solution series FexTi3?xO5, 0 ? x ? 1. Compounds with x > 0.35 have the orthorhombic pseudobrookite structure, and those with x < 0.35 a monoclinic distortion of it. Ferrous ions in the fourfold and eightfold sites give rise to separate quadrupole doublets in the Mössbauer spectra, and thus it has been possible to determine the site occupancy as a function of composition by a least-square analysis of the spectra. The Mössbauer method has also proved to be a sensitive tool for the investigation of the orthorhombic-monoclinic distortion. 相似文献
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Koumi P Green HE Hartley S Jordan D Lahec S Livett RJ Tsang KW Ward DM 《Electrophoresis》2004,25(14):2227-2241
The demand for high-throughput DNA profiling has increased with the introduction of national DNA databases and has led to the development of automated methods of short tandem repeat (STR) profile production; however, a potential bottleneck still exists at the gel electrophoresis stage. Capillary electrophoresis sequencers capable of processing 96 samples with considerably reduced manual intervention are now available. In this paper, we compare the ABI Prism 377 slab-gel sequencer currently used by the Forensic Science Service with three leading capillary array electrophoresis instruments: the ABI Prism 3700, the Amersham MegaBACE 1000 and the 16-capillary ABI Prism 3100. We describe the experiments used to evaluate and validate these platforms for forensic use with the STR multiplex Ampf/STR SGMplus [1, 2], along with comparative data from the ABI Prism 377 sequencer. 相似文献