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Changes in the quality of life in severely disabled people following provision of powered indoor/outdoor chairs
Purpose:To determine the benefits for patients who received an Electric Powered Indoor/outdoor Chair (EPIOC) and to quantify their perceived changes to their quality of life.
Method: Community-based cohort study of all patients provided with an EPIOC over 4 months; and followed up about 3 months later in a community served by a regional wheelchair service in North West London (population about 3.1 million) using the EuroQol EQ-5D with visual analogue scales for each of the 5 dimensions of the EQ-5D.
Results: Sixty-four wheelchair users were assessed initially and 51 completed follow up. Chair users showed no significant improvement in health state as measured by the EQ-5D after EPIOC provision. The visual analogue scales (VASs) indicated that, although perceived overall health state, independence and social life did not appear to improve, the dimensions of mobility, quality of life and pain/discomfort improved significantly on provision of an EPIOC.
Conclusion: EPIOC users reported significant improvements in several important aspects of their lives; not just in mobility (as expected) but also in reduction of pain and discomfort. The use of VASs provided a more holistic set of outcome measures that demonstrate quality of life benefits beyond that of health state alone
Experimental demonstration at 10 Gbit/s of a 2R-regenerator based on the mutual optical feedback between a laser diode and an SOA
A new regenerator concept based on the feedback between a laser diode and an SOA has been tested using an integrated version. Excellent regenerator characteristics, both static and 10Gbit/s dynamic operation, have been obtained
Towards the application of the Maximum Entropy Method to finite temperature Upsilon Spectroscopy
According to the Narnhofer Thirring Theorem interacting systems at finite
temperature cannot be described by particles with a sharp dispersion law. It is
therefore mandatory to develop new methods to extract particle masses at finite
temperature. The Maximum Entropy method offers a path to obtain the spectral
function of a particle correlation function directly. We have implemented the
method and tested it with zero temperature Upsilon correlation functions
obtained from an NRQCD simulation. Results for different smearing functions are
discussed.Comment: Lattice 2000 (Finite Temperature
Quaternionic differential operators
Motivated by a quaternionic formulation of quantum mechanics, we discuss
quaternionic and complex linear differential equations. We touch only a few
aspects of the mathematical theory, namely the resolution of the second order
differential equations with constant coefficients. We overcome the problems
coming out from the loss of the fundamental theorem of the algebra for
quaternions and propose a practical method to solve quaternionic and complex
linear second order differential equations with constant coefficients. The
resolution of the complex linear Schrodinger equation, in presence of
quaternionic potentials, represents an interesting application of the
mathematical material discussed in this paper.Comment: 25 pages, AMS-Te
Red giant collisions in the galactic centre
We simulate collisions involving red-giant stars in the centre of our galaxy.
Such encounters may explain the observed paucity of highly luminous red giants
within the central 0.2pc. The masses of the missing stars are likely to be in
the range 2 to 8 solar masses. Recent models of the galactic centre cluster's
density and velocity distributions are used to calculate two-body collision
rates. In particular we use stellar-evolution models to calculate the number of
collisions a star will have during different evolutionary phases. We find that
the number of two-body collisions per star is \lo 1 in the central 0.1 to 0.2
pc, depending strongly on the galactocentric radius. Using a 3D numerical
hydrodynamics code (SPH) we simulate encounters involving cluster stars of
various masses with 2 and 8 solar-mass red giants. The instantaneous mass loss
in such collisions is rarely enough to destroy either giant. A fraction of the
collisions do, however, lead to the formation of common envelope systems where
the impactor and giant's core are enshrouded by the envelope of the giant. Such
systems may evolve to expel the envelope, leaving a tight binary; the original
giant is destroyed. The fraction of collisions that produce common envelope
systems is sensitive to the local velocity dispersion and hence galactocentric
radius. Using our collision-rate calculations we compute the time-scales for a
giant star to suffer such a collision within the galactic centre. These
time-scales are >10^{9-10}years and so are longer than the lifetimes of stars
more-massive than 2 solar masses. Thus the observed paucity of luminous giants
is unlikely to be due to the formation of common envelope systems as a result
of two-body encounters involving giant stars.Comment: 10 pages, 11 figures, MNRAS (in press
Desiring and critiquing humanity/ability/personhood : disrupting the ability/disability binary
The authors take up the challenge of Goodley and Runswick-Cole’s call to dismantle the ability/disability binary such that those now called ‘disabled’ can unproblematically join the ranks of those who will be counted as human. Using the methodology of collective biography, the six authors explore their own memories of becoming abled, and find in those memories a similar pattern of desire for, and critique of, humanness that Goodley and Runswick-Cole found in the participants in their own study, participants who were categorised as intellectually disabled. We turn to post philosophies to further develop the vocabularies through which the meaning of human can be expanded to include those who are currently viewed as less-than-human or other-to-human in their difference from the norm.
Points of interest:
- In this article the authors use the research method of ‘collective biography’ to explore their first memories of how they became able, and were recognized as normal and human.
- We work with childhood photos to help open up our memories.
- We challenge the taken-for-granted division between the categories normal/abnormal, able/disabled.
- We argue that everybody is different, and that we all change and become able in different ways.
- We are all vulnerable and we all desire to belong in the same world, irrespective of the categories we are placed in
Spatially resolved kinematics of the central regions of M83: hidden mass signatures and the role of supernovae
The barred grand-design spiral M83 (NGC 5236) is one of the most studied
galaxies given its proximity, orientation, and particular complexity.
Nonetheless, many aspects of the central regions remain controversial conveying
our limited understanding of the inner gas and stellar kinematics, and
ultimately of the nucleus evolution.
In this work, we present AO VLT-SINFONI data of its central ~235x140 pc with
an unprecedented spatial resolution of ~0.2 arcsec, corresponding to ~4 pc. We
have focused our study on the distribution and kinematics of the stars and the
ionised and molecular gas by studying in detail the Pa_alpha and Br_gamma
emission, the H_2 1-0S(1) line at 2.122 micron and the [FeII] line at 1.644
micron, together with the CO absorption bands at 2.293 micron and 2.323 micron.
Our results reveal a complex situation where the gas and stellar kinematics are
totally unrelated. Supernova explosions play an important role in shaping the
gas kinematics, dominated by shocks and inflows at scales of tens of parsecs
that make them unsuitable to derive general dynamical properties.
We propose that the location of the nucleus of M83 is unlikely to be related
to the off-centre 'optical nucleus'. The study of the stellar kinematics
reveals that the optical nucleus is a gravitationally bound massive star
cluster with M_dyn = (1.1 \pm 0.4)x10^7 M_sun, formed by a past starburst. The
kinematic and photometric analysis of the cluster yield that the stellar
content of the cluster is well described by an intermediate age population of
log T(yr) = 8.0\pm0.4, with a mass of M \simeq (7.8\pm2.4)x10^6 M_sun.Comment: 14 pages, 10 figures, accepted for publication in Ap
Inference of Planck action constant by a classical fluctuative postulate holding for stable microscopic and macroscopic dynamical systems
The possibility is discussed of inferring or simulating some aspects of
quantum dynamics by adding classical statistical fluctuations to classical
mechanics. We introduce a general principle of mechanical stability and derive
a necessary condition for classical chaotic fluctuations to affect confined
dynamical systems, on any scale, ranging from microscopic to macroscopic
domains. As a consequence we obtain, both for microscopic and macroscopic
aggregates, dimensional relations defining the minimum unit of action of
individual constituents, yielding in all cases Planck action constant.Comment: 14 pages, no figure
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