148,555 research outputs found

    Catalogue of candidate emission-line objects in the Small Magellanic Cloud

    Get PDF
    H\alpha and [O III] narrow band, wide field (7 * 7 degree), CCD images of the Small Magellanic Cloud were compared and a catalogue of candidate planetary nebulae and H\alpha emission-line stars was compiled. The catalogue contains 131 planetary nebulae candidates, 23 of which are already known to be or are probable planetary nebulae or very low excitation objects. Also, 218 emission-line candidates have been identified with 113 already known. Our catalogue therefore provides a useful supplement to those of Meyssonnier & Azzopardi (1993) and Sanduleak, MacConnell & Davis Phillip (1978). Further observations are required to confirm the identity of the unknown objects.Comment: 8 pages, accepted by MNRA

    A Visible Radiation: Interpreting the History of the Eleventh Amendment as Foreign Policy to Circumscribe the Treaty Power

    Get PDF
    In the longstanding debate over the proper place of the Treaty Power in the Constitution\u27s federal structure, on the one hand there are Federalists and on the other hand there are federalists. During the ratification of the Constitution, many Federalists believed the national government needed an expansive Treaty Power to preserve the nascent union. Today, many federalists see such a Treaty Power as a potential threat to the sovereignty of the states. Between 1998 and 2000, the Michigan Law Review published a series of articles by Curtis Bradley and David Golove on competing conceptions of how the Treaty Power fits in the Constitution\u27s federal structure. Bradley argued that federalism delimits the capacity of the national government to create binding national law through the forging of treaties. That is, the national government may not invade the sovereign province of the states by using the Treaty Power to circumvent the restrictions placed on the national government by federalism. In contrast, Golove argued that the national government may use the Treaty Power to legislate in areas generally reserved to the states so long as the Constitution does not explicitly prevent it. Unfortunately, neither author\u27s argument addressed the history of the most important constitutional event bearing on the issue -- the ratification of the Eleventh Amendment

    On K\"ahler conformal compactifications of U(n)U(n)-invariant ALE spaces

    Full text link
    We prove that a certain class of ALE spaces always has a Kahler conformal compactification, and moreover provide explicit formulas for the conformal factor and the Kahler potential of said compactification. We then apply this to give a new and simple construction of the canonical Bochner-K\"ahler metric on certain weighted projective spaces, and also to explicitly construct a family Kahler edge-cone metrics on CP2\mathbb{CP}^2, with singular set CP1\mathbb{CP}^1, having cone angles 2πβ2\pi\beta for all β>0\beta>0. We conclude by discussing how these results can be used to obtain certain well-known Einstein metrics.Comment: 14 page

    Learning Character Strings via Mastermind Queries, with a Case Study Involving mtDNA

    Full text link
    We study the degree to which a character string, QQ, leaks details about itself any time it engages in comparison protocols with a strings provided by a querier, Bob, even if those protocols are cryptographically guaranteed to produce no additional information other than the scores that assess the degree to which QQ matches strings offered by Bob. We show that such scenarios allow Bob to play variants of the game of Mastermind with QQ so as to learn the complete identity of QQ. We show that there are a number of efficient implementations for Bob to employ in these Mastermind attacks, depending on knowledge he has about the structure of QQ, which show how quickly he can determine QQ. Indeed, we show that Bob can discover QQ using a number of rounds of test comparisons that is much smaller than the length of QQ, under reasonable assumptions regarding the types of scores that are returned by the cryptographic protocols and whether he can use knowledge about the distribution that QQ comes from. We also provide the results of a case study we performed on a database of mitochondrial DNA, showing the vulnerability of existing real-world DNA data to the Mastermind attack.Comment: Full version of related paper appearing in IEEE Symposium on Security and Privacy 2009, "The Mastermind Attack on Genomic Data." This version corrects the proofs of what are now Theorems 2 and 4
    corecore