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51.
We study the transition probabilities for the totally asymmetric simple exclusion process (TASEP) on the infinite integer
lattice with a finite, but arbitrary number of first and second class particles. Using the Bethe ansatz we present an explicit
expression of these quantities in terms of the Bethe wave function. In a next step it is proved rigorously that this expression
can be written in a compact determinantal form for the case where the order of the first and second class particles does not
change in time. An independent geometrical approach provides insight into these results and enables us to generalize the determinantal
solution to the multi-class TASEP. 相似文献
52.
María Teresa Gallegos Gunter Ritter 《Advances in Data Analysis and Classification》2018,12(2):179-202
The present paper proposes a new strategy for probabilistic (often called model-based) clustering. It is well known that local maxima of mixture likelihoods can be used to partition an underlying data set. However, local maxima are rarely unique. Therefore, it remains to select the reasonable solutions, and in particular the desired one. Credible partitions are usually recognized by separation (and cohesion) of their clusters. We use here the p values provided by the classical tests of Wilks, Hotelling, and Behrens–Fisher to single out those solutions that are well separated by location. It has been shown that reasonable solutions to a clustering problem are related to Pareto points in a plot of scale balance vs. model fit of all local maxima. We briefly review this theory and propose as solutions all well-fitting Pareto points in the set of local maxima separated by location in the above sense. We also design a new iterative, parameter-free cutting plane algorithm for the multivariate Behrens–Fisher problem. 相似文献
53.
Adverse drug reactions (ADRs) are a major public health problem. Pharmacogenetic testing prior to drug treatment is supposed to considerably alleviate this problem. The state of pharmacogenetic development was assessed by a systematic literature review, supplemented by expert interviews. Analysis of three case examples revealed that - with the exception of thiopurine methyltransferase (TPMT) - studies are lacking which unambiguously prove the clinical value of pharmacogenetic testing. Testing can prevent some, but by far not all ADRs. Since it does not compensate for clinical monitoring, pharmacogenetics can be regarded as add-on technology, applied in addition to established methods. A non-representative, explorative survey conducted amongst members of the German Society of Laboratory Medicine revealed that the demand for testing is limited and has not increased much, although a certain increase is expected in the future. 相似文献
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Gunter Heymann Jan F. Riecken Sudhindra Rayaprol Sandra Christian Rainer Pöttgen Prof. Dr. Hubert Huppertz PD Dr. 《无机化学与普通化学杂志》2007,633(1):77-82
The high‐pressure (HP) modification of CePdSn was synthesized under multianvil high‐pressure (10.5 GPa) high‐temperature (1100 °C) conditions from the normal‐pressure (NP) modification. The structures of both modifications were studied by X‐ray powder and single crystal diffraction: TiNiSi type, Pnma, a = 754.1(2), b = 470.6(1), c = 798.4(3) pm, wR2 = 0.0333, 945 F2 values, 20 variables for NP‐CePdSn and ZrNiAl type, , a = 760.03(5), c = 416.06(3) pm, wR2 = 0.0443, 248 F2 values, 13 variables for HP‐CePdSn. The structural chemistry of both modifications is goverened by platinum centered trigonal prisms. The platinum and tin atoms in NP‐CePdSn and HP‐CePdSn build up a three‐dimensional [PdSn] network in which the cerium atoms fill channels. Susceptibility measurements on HP‐CePdSn reveal an experimental magnetic moment of 2.55(1) μB/Ce atom in the paramagnetic region. At 5 K a paramagnetic‐to‐antiferromagnetic transition is evident from magnetization and specific heat measurements. 相似文献
56.
Ashutosh Sharma R. Khanna Gunter Reiter 《Colloids and surfaces. B, Biointerfaces》1999,14(1-4):223-235
We present experimental results on the instability and dewetting of thin liquid polydimethylsiloxane (PDMS) films intercalated between an aqueous medium and a silicon wafer grafted with PDMS ‘brushes’. This is a thin film analog of the precorneal thin mucus coating sandwiched between the aqueous tear film and the glycocalyx carrying corneal epithelial surface. Lowering of the PDMS–water interfacial tension by a surfactant results in dewetting even of micrometer thick films within a few minutes. The instability appears to be induced by a long range non-classical DLVO force which has the same decay behavior as the nonretarded van der Waals force, but a magnitude which is about 2–3 orders higher. Implications for the breakup of the precorneal mucus layer and the tear film are discussed. 相似文献
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Masumi Asakawa Peter R. Ashton Vincenzo Balzani Alberto Credi Christoph Hamers Gunter Mattersteig Marco Montalti Andrew N. Shipway Neil Spencer J. Fraser Stoddart Malcolm S. Tolley Margherita Venturi Andrew J. P. White David J. Williams 《Angewandte Chemie (International ed. in English)》1998,37(3):333-337
A mechanical switch in a [2]catenane , made up of a cyclobis(paraquat-p-phenylene) tetracation interlocked with a macrocyclic polyether containing a redox-active tetrathiafulvalene (TTF) unit and a 1,5-dioxynaphthalene ring system, can be thrown either chemically or electrochemically. The neutral TTF unit resides “inside” the tetracationic cyclophane in the reduced state and “alongside” it in the oxidized species (TTF+/ TTF2+). Switching between the reduced (I4+) and oxidized state (I5+(I6+)) is accompanied by a dramatic color change. 相似文献
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