21,666 research outputs found

    Analyzing Visual Mappings of Traditional and Alternative Music Notation

    Full text link
    In this paper, we postulate that combining the domains of information visualization and music studies paves the ground for a more structured analysis of the design space of music notation, enabling the creation of alternative music notations that are tailored to different users and their tasks. Hence, we discuss the instantiation of a design and visualization pipeline for music notation that follows a structured approach, based on the fundamental concepts of information and data visualization. This enables practitioners and researchers of digital humanities and information visualization, alike, to conceptualize, create, and analyze novel music notation methods. Based on the analysis of relevant stakeholders and their usage of music notation as a mean of communication, we identify a set of relevant features typically encoded in different annotations and encodings, as used by interpreters, performers, and readers of music. We analyze the visual mappings of musical dimensions for varying notation methods to highlight gaps and frequent usages of encodings, visual channels, and Gestalt laws. This detailed analysis leads us to the conclusion that such an under-researched area in information visualization holds the potential for fundamental research. This paper discusses possible research opportunities, open challenges, and arguments that can be pursued in the process of analyzing, improving, or rethinking existing music notation systems and techniques.Comment: 5 pages including references, 3rd Workshop on Visualization for the Digital Humanities, Vis4DH, IEEE Vis 201

    Noether's Theorem for Fractional Optimal Control Problems

    Full text link
    We begin by reporting on some recent results of the authors (Frederico and Torres, 2006), concerning the use of the fractional Euler-Lagrange notion to prove a Noether-like theorem for the problems of the calculus of variations with fractional derivatives. We then obtain, following the Lagrange multiplier technique used in (Agrawal, 2004), a new version of Noether's theorem to fractional optimal control systems.Comment: To be presented at FDA'06 - 2nd IFAC Workshop on Fractional Differentiation and its Applications, 19-21 July 2006, Porto, Portugal. Accepted (07-March-2006) for the Conference Proceeding

    Decomposing the real line into Borel sets closed under addition

    Get PDF
    We consider decompositions of the real line into pairwise disjoint Borel pieces so that each piece is closed under addition. How many pieces can there be? We prove among others that the number of pieces is either at most 3 or uncountable, and we show that it is undecidable in ZFCZFC and even in the theory ZFC+c=ω2ZFC + \mathfrak{c} = \omega_2 if the number of pieces can be uncountable but less than the continuum. We also investigate various versions: what happens if we drop the Borelness requirement, if we replace addition by multiplication, if the pieces are subgroups, if we partition (0,)(0,\infty), and so on

    A case report of Parry Romberg Syndrome initially presenting as periodontitis

    Get PDF
    Parry Romberg Syndrome (PRS) is a rare disorder of progressive hemifacial atrophy, involving soft tissues, fat and occasionally bone. It can co-exist with presentations of Morphea. We describe an unusual case of persistent periodontal and alveolar destruction associated with PRS. A 56-year-old African female initially presented with persistent periodontal destruction, which showed minimal response to conventional periodontal treatment. After non-surgical treatment, surgical debridement followed by extraction of the two right maxillary incisor teeth was required to halt the periodontal destruction. Atrophy was not limited to the periodontal tissues. Multidisciplinary care and extensive investigations were required to diagnose PRS. Once the PRS has stabilised, adipose tissue transplants will be required to improve the facial appearance. We highlight the need for extensive investigations and a multidisciplinary approach to diagnose rare systemic causes for recalcitrant periodontal disease

    Fractional Noether's theorem in the Riesz-Caputo sense

    Full text link
    We prove a Noether's theorem for fractional variational problems with Riesz-Caputo derivatives. Both Lagrangian and Hamiltonian formulations are obtained. Illustrative examples in the fractional context of the calculus of variations and optimal control are given.Comment: Accepted (25/Jan/2010) for publication in Applied Mathematics and Computatio

    Regulation of plasmid-encoded isoprene metabolism in Rhodococcus, a representative of an important link in the global isoprene cycle

    Get PDF
    Emissions of biogenic volatile organic compounds (VOCs) form an important part of the global carbon cycle, comprising a significant proportion of net ecosystem productivity. They impact atmospheric chemistry and contribute directly and indirectly to greenhouse gases. Isoprene, emitted largely from plants, comprises one third of total VOCs, yet in contrast to methane, which is released in similar quantities, we know little of its biodegradation. Here, we report the genome of an isoprene degrading isolate, Rhodococcus sp. AD45, and, using mutagenesis shows that a plasmid-encoded soluble di-iron centre isoprene monooxygenase (IsoMO) is essential for isoprene metabolism. Using RNA sequencing (RNAseq) to analyse cells exposed to isoprene or epoxyisoprene in a substrate-switch time-course experiment, we show that transcripts from 22 contiguous genes, including those encoding IsoMO, were highly upregulated, becoming among the most abundant in the cell and comprising over 25% of the entire transcriptome. Analysis of gene transcription in the wild type and an IsoMO-disrupted mutant strain showed that epoxyisoprene, or a subsequent product of isoprene metabolism, rather than isoprene itself, was the inducing molecule. We provide a foundation of molecular data for future research on the environmental biological consumption of this important, climate-active compound

    Collective relaxation of stellar systems revisited

    Full text link
    The chaos in stellar systems is studied using the theory of dynamical systems and the Van Kampen stochastic differential equation approach. The exponential instability (chaos) of spherical N-body gravitating systems, already known previously, is confirmed. The characteristic timescale of that instability is estimated confirming the collective relaxation time obtained by means of the Maupertuis principle.Comment: A & A (in press), 3 pages, to match the published versio
    corecore