54 research outputs found

    Locally Finite Families, Completely Separated Sets and Remote Points

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    It is shown that if X is a nonpseudocompact space with a σ-locally finite π-base, then X has remote points. Within the class of spaces possessing a σ-locally finite π-base, this result extends the work of Chae and Smith, because their work utilized normality to achieve complete separation. It provides spaces which have remote points, where the spaces do not satisfy the conditions required in the previous works by Dow, by van Douwen, by van Mill, or by Peters. The lemma: Let X be a space and let {Cε: € \u3c α} be a locally finite family of cozero sets of X. Let {Zε: € \u3c α } be a family of zero sets of X such that for each € \u3c α, Zε с Cε. Then ∪ε\u3cα Zε is completely separated from X/∪εCε , is a fundamental tool in this work. An example is given which demonstrates the value of this tool. The example also refutes an appealing conjecture -- a conjecture for which the authors found that there existed significant confusion within the topological community as to its truth or falsity

    Fantastically reasonable: ambivalence in the representation of science and technology in super-hero comics

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    A long-standing contrast in academic discussions of science concerns its perceived disenchanting or enchanting public impact. In one image, science displaces magical belief in unknowable entities with belief in knowable forces and processes and reduces all things to a single technical measure. In the other, science is itself magically transcendent, expressed in technological adulation and an image of scientists as wizards or priests. This paper shows that these contrasting images are also found in representations of science in super-hero comics, which, given their lowly status in Anglo-American culture, would seem an unlikely place to find such commonality with academic discourse. It is argued that this is evidence that the contrast constitutes an ambivalence arising from the dilemmas that science poses; they are shared rhetorics arising from and reflexively feeding a set of broad cultural concerns. This is explored through consideration of representations of science at a number of levels in the comics, with particular focus on the science-magic constellation, and enchanted and disenchanted imagery in representations of technology and scientists. It is concluded that super-hero comics are one cultural arena where the public meaning of science is actively worked out, an activity that unites “expert” and “non-expert” alike

    Diet of breeding northern Goshawks in the Coast Range of Oregon

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    Volume: 34Start Page: 339End Page: 34

    A molecular phylogenetic framework for the Muricidae, a diverse family of carnivorous gastropods

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    With over 1600 extant described species, the Muricidae are one of the most species-rich and morphologically diverse families of molluscs. As predators of molluscs, polychaetes, anthozoans barnacles and other invertebrates, they form an important component of many benthic communities. Traditionally, the classification of muricids at specific and generic levels has been based primarily on shells, while subfamilies have been defined largely by radular morphology, although the composition and relationships of supra-generic groups have never been studied exhaustively. Here we present the phylogenetic relationships of 77 muricid species belonging to nine of the ten currently recognized subfamilies, based on Bayesian inference and Maximum Likelihood analyses of partial sequences of three mitochondrial (12S, 16S and COI) and one nuclear (28S) genes. The resulting topologies are discussed with respect to traditional subfamilial arrangements, and previous anatomical and molecular findings. We confirm monophyly of each of the subfamilies Ergalataxinae, Rapaninae, Coralliophilinae, Haustrinae, Ocenebrinae and Typhinae as previously defined, but earlier concepts of Muricinae, Trophoninae and Muricopsinae are shown to be polyphyletic. Based on our phylogenetic hypothesis, a new arrangement of these subfamilies is proposed. (C) 2010 Elsevier Inc. All rights reserved
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