21,666 research outputs found
Analyzing Visual Mappings of Traditional and Alternative Music Notation
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
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
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 and even in the theory
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 , and so on
A case report of Parry Romberg Syndrome initially presenting as periodontitis
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
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
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
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
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