852 resultados para Birkhoff and Von Neumann ergodic theorems
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We describe an unprecedented radiation of sanguinicolid blood flukes ( Digenea: Sanguinicolidae) from two species of Labridae (Choerodon venustus and C. cauteroma), seven species of Mullidae (Mulloidichthys vanicolensis, Parupeneus barberinoides, P. barberinus, P. bifasciatus, P. cyclostomus, P. indicus and P. multifasciatus) and ten species of Siganidae (Siganus argenteus, S. corallinus, S. doliatus, S. fuscescens, S. lineatus, S. margaritiferus, S. puellus, S. punctatus, S. virgatus and S. vulpinus) from sites off Australia and Palau. The flukes were morphologically similar in having the combination of a long thread-like body, tegumental spines in lateral transverse rows, a vestigial oral sucker bearing concentric rows of fine spines, an H-shaped intestine, a cirrussac, a notch level with the male genital pore, a lateral or post-ovarian uterus, a uterine chamber and separate genital pores. These species are divided into two genera on the basis of testis number. Sanguinicolids from Siganus fuscescens have a single large testis between the intestinal bifurcation and the ovary and are placed in Ankistromeces Nolan & Cribb, 2004. Species from the remaining nine species of Siganidae, Labridae and Mullidae are placed in Phthinomita n. g.; these species have two testes, the anterior testis being large and between the intestinal bifurcation and the ovary whereas the small posterior testis is at the posterior end of the body and appears rudimentary or degenerate and probably non-functional. The second internal transcribed spacer (ITS2) of ribosomal DNA ( rDNA) from 29 host/parasite/location combinations (h/p/l) was sequenced together with that of Ankistromeces mariae Nolan & Cribb, 2004 for comparison. From 135 samples we found 19 distinct genotypes which were interpreted as representing at least that many species. Replicate sequences were obtained for 25 of 30 h/p/l combinations ( including A. mariae); there was no intraspecific variation between replicates sequences for any of these. Interspecific variation ranged from 1 - 41 base differences (0.3 - 12.7% sequence divergence). The 19 putative species were difficult to recognise by morphological examination. We describe 13 new species; we do not describe (= name) six species characterised solely by molecular sequences and three putative species for which morphological data is available but for which molecular data is not. We have neither morphological nor molecular data for sanguinicolids harboured in five hosts species ( Siganus margaritiferus, S. puellus, Choerodon cauteroma, Parupeneus indicus and P. multifasciatus) in which we have seen infections. Where host species were infected in different localities they almost always harboured distinct species. Some host species ( for example, S. argenteus and S. lineatus from Lizard Island) harboured two or three species in a single geographical location. This suggests that, for parts of this system, parasite speciation has outstripped host speciation. Distance analysis of ITS2 showed species from each host family ( Siganidae, Mullidae and Labridae) did not form monophyletic clades to the exclusion of species from other host families. However, a host defined clade was formed by the sequences from sanguinicolids from S. fuscescens.
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This chapter undertakes the first examination of the role the fine arts play in Thomas Bernhard’s prose works. Though not as prominent as the role of music, painting and the fine arts play a crucial role in Frost and Alte Meister; these two novels coincidentally also happen to be the first and last novels written by Bernhard. This chapter takes its cue from the positive role awarded to Francis Bacon in the novel Das Kalkwerk. Comparing and contrasting the relation and influence between the art of Bacon and the literature of Bernhard, I am able to demonstrate a number of surprising analogies. Following a brief biographical synopsis, I focus on four aesthetic operations that are crucial to both artists. Using the key terms of ‘middle way’, ‘variation’, ‘vibration’ and ‘mediation’, I am able to uncover surprising similarities between the novels and the paintings. These hidden connections are further confirmed by looking at the two artists’ shared major motifs, namely the slaughterhouse, the scream, the relation between animals and humans, and pain. This bleak outlook on the state of human civilisation that these two major artists of the end of the 20th century share, embodies both a warning and a prophesy for the 21st century.
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This article examines the multi-layered interrelation between Gerhard Roth’s writing and film. It charts the corresponding relationship of his early books to their accompanying television documentaries. The main focus of this essay however is on the film adaptation of Stille Ozean (1980) and Landäufiger Tod (1984), the two major novels in his cycle Archive des Shweigens. Supplemented by a look at the two radically different adaptations of his volume of topographical essays on Vienna called Eine Reise in das Innere von Wien (1991), the article also provides a summary overview of the seven dramas written by Roth for Austrian television in the 1990s, some of which were directed by his son Thomas. Finally Roth's approach to the medium of film is being discussed by drawing on the 59 reviews he published between 1995 and 1997 as a film critic for the Austrian magazine NEWS.
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W. G. Sebald’s special interest in marginal authors shaped his critical perception of Austrian postwar writers. Focusing on his critical writings on Herbert Achternbusch and the schizophrenic poet Ernst Herbeck—considered by Sebald as paradigms of a disregarded, “minor” form of literature—this essay demonstrates how on the one hand Sebald placed their texts within an anthropological context of an “untamed thinking” (pensée sauvage) and how on the other he sought to reverse the standard practice of evaluating the literary value of “minor” writers from the perspective of established authors. As this critical approach indirectly suggests, literary criticism needs to adopt a “minor” stance to be truly able to unlock the meaning of normally marginalised texts.
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We propose and investigate a method for the stable determination of a harmonic function from knowledge of its value and its normal derivative on a part of the boundary of the (bounded) solution domain (Cauchy problem). We reformulate the Cauchy problem as an operator equation on the boundary using the Dirichlet-to-Neumann map. To discretize the obtained operator, we modify and employ a method denoted as Classic II given in [J. Helsing, Faster convergence and higher accuracy for the Dirichlet–Neumann map, J. Comput. Phys. 228 (2009), pp. 2578–2576, Section 3], which is based on Fredholm integral equations and Nyström discretization schemes. Then, for stability reasons, to solve the discretized integral equation we use the method of smoothing projection introduced in [J. Helsing and B.T. Johansson, Fast reconstruction of harmonic functions from Cauchy data using integral equation techniques, Inverse Probl. Sci. Eng. 18 (2010), pp. 381–399, Section 7], which makes it possible to solve the discretized operator equation in a stable way with minor computational cost and high accuracy. With this approach, for sufficiently smooth Cauchy data, the normal derivative can also be accurately computed on the part of the boundary where no data is initially given.
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∗ The final version of this paper was sent to the editor when the author was supported by an ARC Small Grant of Dr. E. Tarafdar.
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The purpose of this paper is (1) to highlight some recent and heretofore unpublished results in the theory of multiplier sequences and (2) to survey some open problems in this area of research. For the sake of clarity of exposition, we have grouped the problems in three subsections, although several of the problems are interrelated. For the reader’s convenience, we have included the pertinent definitions, cited references and related results, and in several instances, elucidated the problems by examples.
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Mathematics Subject Classification: 26A16, 26A33, 46E15.