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An education and negotiation of differences: the âschoolingâ experiences of English-speaking Canadian children growing up with polio during the 1940s and 1950s
In this paper we present oral narratives focusing on schooling experiences of Canadians who lived with polio as children between 1940 and 1959. We argue that disabled students with polio received an education about the differences ascribed to them by individuals in authority (teachers, principals), by other young people, and through the dominant negative discourses of polio and normalizing, ableist practices of schooling. Using narrative accounts from participantsâ interviews, we analyze their school experiences of difference: inaccessible physical and temporal spaces, bullying at school, exclusion from classes, and negotiating youth culture related to shoes, clothes and friendships. However, participants were not passive and they discussed how, along with families, they negotiated and occasionally defied normalizing processes. This research gives voice to a generation of disabled English-speaking Canadians, whose stories about school have not been heard before
Objective structured clinical examinations (OSCEs), psychiatry and the clinical assessment of skills and competencies (CASC) : same evidence, different judgement
Background: The Objective Structured Clinical Examination (OSCE), originally developed in the 1970âs, has been
hailed as the "gold standard" of clinical assessments for medical students and is used within medical schools
throughout the world. The Clinical assessment of Skills and Competencies (CASC) is an OSCE used as a clinical
examination gateway, granting access to becoming a senior Psychiatrist in the UK.
Discussion: Van der Vleutenâs utility model is used to examine the CASC from the viewpoint of a senior
psychiatrist. Reliability may be equivalent to more traditional examinations. Whilst the CASC is likely to have
content validity, other forms of validity are untested and authenticity is poor. Educational impact has the potential
to change facets of psychiatric professionalism and influence future patient care. There are doubts about
acceptability from candidates and more senior psychiatrists.
Summary: Whilst OSCEs may be the best choice for medical student examinations, their use in post graduate
psychiatric examination in the UK is subject to challenge on the grounds of validity, authenticity and educational
impact
Flipped Angles and Phases: A Systematic Study
We discuss systematically the fermion mass and mixing matrices in a generic
\linebreak field-theoretical flipped model, with particular
applications to neutrino and baryon number-changing physics. We demonstrate
that the different quark flavour branching ratios in proton decay are related
to the Cabibbo-Kobayashi-Maskawa angles, whereas the lepton flavour branching
ratios are undetermined. The light neutrino mixing angles observable via
oscillation effects are related to the heavy conjugate (right-handed) neutrino
mass matrix, which also plays a key role in cosmological baryogenesis. The
ratios of neutrino and charged lepton decay modes in baryon decay may also be
related to neutrino oscillation parameters. Plausible Ans\"atze for the
generation structure of coupling matrices motivate additional relations between
physical observables, and yield a satisfactory baryon asymmetry.Comment: 13 pages, no figures, latex (twice), CERN-TH.6842/93, UMN-TH-1130/93,
CTP-TAMU-11/9
Implications of Anomalous U(1) Symmetry in Unified Models: the Flipped SU(5) x U(1) Paradigm
A generic feature of string-derived models is the appearance of an anomalous
Abelian U(1)_A symmetry which, among other properties, constrains the Yukawa
couplings and distinguishes the three families from each other. In this paper,
we discuss in a model-independent way the general constraints imposed by such a
U(1)_A symmetry on fermion masses, R-violating couplings and proton-decay
operators in a generic flipped SU(5) x U(1)' model. We construct all possible
viable fermion mass textures and give various examples of effective low-energy
models which are distinguished from each other by their different predictions
for B-, L- and R-violating effects. We pay particular attention to predictions
for neutrino masses, in the light of the recent Super-Kamiokande data.Comment: 28 pages, reference adde
Outer planet mission guidance and navigation for spinning spacecraft
The orbit determination accuracies, maneuver results, and navigation system specification for spinning Pioneer planetary probe missions are analyzed to aid in determining the feasibility of deploying probes into the atmospheres of the outer planets. Radio-only navigation suffices for a direct Saturn mission and the Jupiter flyby of a Jupiter/Uranus mission. Saturn ephemeris errors (1000 km) plus rigid entry constraints at Uranus result in very high velocity requirements (140 m/sec) on the final legs of the Saturn/Uranus and Jupiter/Uranus missions if only Earth-based tracking is employed. The capabilities of a conceptual V-slit sensor are assessed to supplement radio tracking by star/satellite observations. By processing the optical measurements with a batch filter, entry conditions at Uranus can be controlled to acceptable mission-defined levels (+ or - 3 deg) and the Saturn-Uranus leg velocity requirements can be reduced by a factor of 6 (from 139 to 23 m/sec) if nominal specified accuracies of the sensor can be realized
Single top production and decay at next-to-leading order
We present the results of a next-to-leading order analysis of single top
production including the decay of the top quark. Radiative effects are included
both in the production and decay stages, using a general subtraction method.
This calculation gives a good treatment of the jet activity associated with
single top production. We perform an analysis of the single top search at the
Tevatron, including a consideration of the main backgrounds, many of which are
also calculated at next-to-leading order.Comment: 35 pages + 15 figures, revtex
Production of a Z boson and two jets with one heavy-quark tag
We present a next-to-leading-order calculation of the production of a Z boson
with two jets, one or more of which contains a heavy quark (Q=c,b). We show
that the cross section with only one heavy-quark jet is larger than that with
two heavy-quark jets at both the Fermilab Tevatron and the CERN LHC. These
processes are the dominant irreducible backgrounds to a Higgs boson produced in
association with a Z boson, followed by h->bb. Our calculation makes use of a
heavy-quark distribution function, which resums collinear logarithms and makes
the next-to-leading-order calculation tractable.Comment: 11 pages, 5 figures. Erratum adde
The Mass Assembly Histories of Galaxies of Various Morphologies in the GOODS Fields
We present an analysis of the growth of stellar mass with cosmic time
partitioned according to galaxy morphology. Using a well-defined catalog of
2150 galaxies based, in part, on archival data in the GOODS fields, we assign
morphological types in three broad classes (Ellipticals, Spirals,
Peculiar/Irregulars) to a limit of z_AB=22.5 and make the resulting catalog
publicly available. We combine redshift information, optical photometry from
the GOODS catalog and deep K-band imaging to assign stellar masses. We find
little evolution in the form of the galaxy stellar mass function from z~1 to
z=0, especially at the high mass end where our results are most robust.
Although the population of massive galaxies is relatively well established at
z~1, its morphological mix continues to change, with an increasing proportion
of early-type galaxies at later times. By constructing type-dependent stellar
mass functions, we show that in each of three redshift intervals, E/S0's
dominate the higher mass population, while spirals are favored at lower masses.
This transition occurs at a stellar mass of 2--3 times 10^{10} Msun at z~0.3
(similar to local studies) but there is evidence that the relevant mass scale
moves to higher mass at earlier epochs. Such evolution may represent the
morphological extension of the ``downsizing'' phenomenon, in which the most
massive galaxies stop forming stars first, with lower mass galaxies becoming
quiescent later. We infer that more massive galaxies evolve into spheroidal
systems at earlier times, and that this morphological transformation may only
be completed 1--2 Gyr after the galaxies emerge from their active star forming
phase. We discuss several lines of evidence suggesting that merging may play a
key role in generating this pattern of evolution.Comment: 24 pages, 1 table, 8 figures, accepted for publication in Ap
Bose-Einstein Final State Symmetrization for Event Generators of Heavy Ion Collisions
We discuss algorithms which allow to calculate identical two-particle
correlations from numerical simulations of relativistic heavy ion collisions. A
toy model is used to illustrate their properties.Comment: Talk given at CRIS'98 (Catania, June 8-12, 1998), to appear in
"CRIS'98: Measuring the size of things in the Universe: HBT interferometry
and heavy ion physics", (S. Costa et al., eds.), World Scientific, Singapore,
1998. (10 pages Latex, 1 eps-figure, extended version of conference
proceedings, Fig1 a,b added and corresponding discussion enlarged
Bose-Einstein Correlations in a Space-Time Approach to e+ e- Annihilation into Hadrons
A new treatment of Bose-Einstein correlations is incorporated in a space-time
parton-shower model for e+ e- annihilation into hadrons. Two alternative
afterburners are discussed, and we use a simple calculable model to demonstrate
that they reproduce successfully the size of the hadron emission region. One of
the afterburners is used to calculate two-pion correlations in e+ e- -> Z^0 ->
hadrons and e+ e- -> W+ W- -> hadrons. Results are shown with and without
resonance decays, for correlations along and transverse to the thrust jet axis
in these two classes of events.Comment: 30 pages, Latex, 8 figure
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