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Composition: interaction and collaboration
For more than two hundred years it has been assumed by those engaged in the production of conservatoire-based music that a composition is best written by a single individual. It has been assumed that the most effective way to communicate a composition is through the exclusive means of the notated score. It has been assumed that the processes of performance and composition should be separate disciplines and that in general, the role of performers should be restricted merely to that of the interpretation of notated music. This thesis presents a challenge to these assumptions through the presentation of a folio of compositions that have each been written through processes based not only on notation, but also in improvisation and various other collaborative aural and oral means. This folio is accompanied by a written discussion of the reasons for wishing to compose music in such a way. In Part One of the written discussion I argue that the tradition of Western art music has reached a point of crisis. This is a crisis that is the result of a growing imbalance between literate and oral modes of thought and expression. I argue that the technology of notation is only partially useful as a tool for composition and communication. Conversely, I discuss what can and has been achieved by musicians when they allow non-notation based processes to form a significant part of the processes of the composition and performance of music. In Part Two I consider the nature of the skills of improvisation. I argue that the practice of improvisation holds part of the key to the regeneration of the conservatoire music tradition and that it is a skill that should serve to undergin an elements of a player's musicianship. In Part Three I discuss some of the more practical considerations of the techniques used in the composition of the music presented in Part Four of the thesis. I attempt to show that through effecting a balance within the composition process between notated elements scored by a single composer, and improvised/realised elements written within the context of an ensemble, a practice can be developed that has implications not only for traditional assumptions of composition, but which serves to question the whole way in which our culture traditionally organises and structures its institutions of education and performance. Part Four takes the form of a recorded folio of works that have been composed as the result of collaborations between the ensembles that perform them and myself
as a director
The definitive position of headache among the major public health challenges. An end to the slippery slope of disregard
[No abstract available
Current Status of Simulations
As the title suggests, the purpose of this chapter is to review the current
status of numerical simulations of black hole accretion disks. This chapter
focuses exclusively on global simulations of the accretion process within a few
tens of gravitational radii of the black hole. Most of the simulations
discussed are performed using general relativistic magnetohydrodynamic (MHD)
schemes, although some mention is made of Newtonian radiation MHD simulations
and smoothed particle hydrodynamics. The goal is to convey some of the exciting
work that has been going on in the past few years and provide some speculation
on future directions.Comment: 15 pages, 14 figures, to appear in the proceedings of the ISSI-Bern
workshop on "The Physics of Accretion onto Black Holes" (8-12 October 2012
Measurement of the Charged Multiplicities in b, c and Light Quark Events from Z0 Decays
Average charged multiplicities have been measured separately in , and
light quark () events from decays measured in the SLD experiment.
Impact parameters of charged tracks were used to select enriched samples of
and light quark events, and reconstructed charmed mesons were used to select
quark events. We measured the charged multiplicities:
,
, from
which we derived the differences between the total average charged
multiplicities of or quark events and light quark events: and . We compared
these measurements with those at lower center-of-mass energies and with
perturbative QCD predictions. These combined results are in agreement with the
QCD expectations and disfavor the hypothesis of flavor-independent
fragmentation.Comment: 19 pages LaTex, 4 EPS figures, to appear in Physics Letters
Modeling the Subsurface Structure of Sunspots
While sunspots are easily observed at the solar surface, determining their
subsurface structure is not trivial. There are two main hypotheses for the
subsurface structure of sunspots: the monolithic model and the cluster model.
Local helioseismology is the only means by which we can investigate
subphotospheric structure. However, as current linear inversion techniques do
not yet allow helioseismology to probe the internal structure with sufficient
confidence to distinguish between the monolith and cluster models, the
development of physically realistic sunspot models are a priority for
helioseismologists. This is because they are not only important indicators of
the variety of physical effects that may influence helioseismic inferences in
active regions, but they also enable detailed assessments of the validity of
helioseismic interpretations through numerical forward modeling. In this paper,
we provide a critical review of the existing sunspot models and an overview of
numerical methods employed to model wave propagation through model sunspots. We
then carry out an helioseismic analysis of the sunspot in Active Region 9787
and address the serious inconsistencies uncovered by
\citeauthor{gizonetal2009}~(\citeyear{gizonetal2009,gizonetal2009a}). We find
that this sunspot is most probably associated with a shallow, positive
wave-speed perturbation (unlike the traditional two-layer model) and that
travel-time measurements are consistent with a horizontal outflow in the
surrounding moat.Comment: 73 pages, 19 figures, accepted by Solar Physic
Multiwavelength studies of MHD waves in the solar chromosphere: An overview of recent results
The chromosphere is a thin layer of the solar atmosphere that bridges the
relatively cool photosphere and the intensely heated transition region and
corona. Compressible and incompressible waves propagating through the
chromosphere can supply significant amounts of energy to the interface region
and corona. In recent years an abundance of high-resolution observations from
state-of-the-art facilities have provided new and exciting ways of
disentangling the characteristics of oscillatory phenomena propagating through
the dynamic chromosphere. Coupled with rapid advancements in
magnetohydrodynamic wave theory, we are now in an ideal position to thoroughly
investigate the role waves play in supplying energy to sustain chromospheric
and coronal heating. Here, we review the recent progress made in
characterising, categorising and interpreting oscillations manifesting in the
solar chromosphere, with an impetus placed on their intrinsic energetics.Comment: 48 pages, 25 figures, accepted into Space Science Review
The burden of headache disorders in the Eastern Mediterranean Region, 1990-2016: Findings from the Global Burden of Disease study 2016
Objectives: Using the findings of the Global Burden of Disease Study (GBD), we report the burden of primary headache disorders in the Eastern Mediterranean Region (EMR) from 1990 to 2016. Methods: We modelled headache disorders using DisMod-MR 2.1 Bayesian meta-regression tool to ensure consistency between prevalence, incidence, and remission. Years lived with disability (YLDs) were calculated by multiplying prevalence and disability weight (DW) of migraine and tension-type headache (TTH). We assumed primary headache disorders as non-fatal, so their YLD is equal to disability-adjusted life years (DALYs). Results: Migraine and TTH were the second and twentieth leading causes of YLDs in EMR. Between 1990 and 2016, the absolute YLD numbers of migraine and TTH increased from 2.3 million (95 uncertainty interval (UI): 1.5-3.2) to 4.7 million (95UI: 3-6.5) and from 383 thousand (95UI: 240-562) to 816 thousand (95UI: 516-1221), respectively. During the same period, age-standardised YLD rates of migraine and TTH in EMR increased by 0.7 and 2.5, respectively, in comparison to a small decrease in the global rates (0.2 decrease in migraine and TTH). The bulk of burden due to headache occurred in the 30-49 year age group, with a peak at ages 35-44 years. The age-standardised YLD rates of both headache disorders were higher in women with female to male ratio of 1.69 for migraine and 1.38 for TTH. All countries of the EMR except for Somalia and Djibouti had higher age-standardised YLD rates for migraine and TTH in compare to the global rates. Libya and Saudi Arabia had the highest increase in age-standardised YLD rates of migraine and TTH, respectively. Conclusion: The findings of this study show that primary headache disorders are a major and a growing cause of disability in EMR. Since 1990, burden of primary headache disorders has constantly been higher in EMR compared to rest of the world, which indicates that health systems in EMR must focus further on developing and implementing preventive and management strategies to control headache. © 2019 The Author(s)
The burden of headache disorders in the Eastern Mediterranean Region, 1990-2016: Findings from the Global Burden of Disease study 2016
Objectives: Using the findings of the Global Burden of Disease Study (GBD), we report the burden of primary headache disorders in the Eastern Mediterranean Region (EMR) from 1990 to 2016. Methods: We modelled headache disorders using DisMod-MR 2.1 Bayesian meta-regression tool to ensure consistency between prevalence, incidence, and remission. Years lived with disability (YLDs) were calculated by multiplying prevalence and disability weight (DW) of migraine and tension-type headache (TTH). We assumed primary headache disorders as non-fatal, so their YLD is equal to disability-adjusted life years (DALYs). Results: Migraine and TTH were the second and twentieth leading causes of YLDs in EMR. Between 1990 and 2016, the absolute YLD numbers of migraine and TTH increased from 2.3 million (95 uncertainty interval (UI): 1.5-3.2) to 4.7 million (95UI: 3-6.5) and from 383 thousand (95UI: 240-562) to 816 thousand (95UI: 516-1221), respectively. During the same period, age-standardised YLD rates of migraine and TTH in EMR increased by 0.7 and 2.5, respectively, in comparison to a small decrease in the global rates (0.2 decrease in migraine and TTH). The bulk of burden due to headache occurred in the 30-49 year age group, with a peak at ages 35-44 years. The age-standardised YLD rates of both headache disorders were higher in women with female to male ratio of 1.69 for migraine and 1.38 for TTH. All countries of the EMR except for Somalia and Djibouti had higher age-standardised YLD rates for migraine and TTH in compare to the global rates. Libya and Saudi Arabia had the highest increase in age-standardised YLD rates of migraine and TTH, respectively. Conclusion: The findings of this study show that primary headache disorders are a major and a growing cause of disability in EMR. Since 1990, burden of primary headache disorders has constantly been higher in EMR compared to rest of the world, which indicates that health systems in EMR must focus further on developing and implementing preventive and management strategies to control headache. © 2019 The Author(s)
Precision measurement of the deuteron spin structure function
We report on a high-statistics measurement of the deuteron spin structure function g[sup d][sub 1] at a beam energy of 29 GeV in the kinematic range 0.029 < x < 0.8 and 1 < Q2 < 10 (GeV/c)2. The integral Gamma [sup d][sub 1] = (integral)[sup 1][sub 0]g[sup d][sub 1]dx evaluated at fixed Q2 = 3 (GeV/c)2 gives 0.042 ± 0.003(stat) ± 0.004(syst). Combining this result with our earlier measurement of g[sup p][sub 1], we find Gamma [sup p][sub 1]- Gamma [sup n][sub 1] = 0.163 ± 0.010(stat) ± 0.016(syst), which agrees with the prediction of the Bjorken sum rule with O( alpha [sup 3][sub s]) corrections, Gamma [sup p][sub 1]- Gamma [sup n][sub 1] = 0.171 ± 0.008. We find the quark contribution to the proton helicity to be Delta q = 0.30 ± 0.06
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