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Imagining inclusive teachers: contesting policy assumptions in relation to the development of inclusive practice in schools
In this paper we reflect on data from two research projects in which inclusive practice in schools is at issue, in the light of wider field experience (our own and others’) of school and teacher development. We question what we understand to be relatively common, implicit policy assumptions about how teachers develop, by examining the way in which teachers are portrayed and located in these projects. The examples discussed in this paper draw on experience in Lao PDR and Bangladesh, critically exploring teachers’ roles, position and agency in practice. Similarities and differences rooted in cultural, political and institutional contexts highlight in a very productive way the significance and potential dangers of policy assumptions about teachers within the process of development.
In Bangladesh, a success story is presented: the case of a group of schools in which an institutional context for learning appears to sustain teachers’ commitment and motivation, with the effect of creating meaningful outcomes for young people who were previously outside the education system. These data raise questions about the significance of institutional context to teachers’ practices, and questions about approaches to teacher development which omit consideration of that context by, for example, focusing inadvertently on features of individual teachers.
We then consider teachers’ responses to the movement for inclusive education in a school in the Lao PDR since 2004. Inclusion here was understood to require a significant shift in teacher identity and a movement away from authoritative pedagogy towards the facilitation of a pedagogy which aimed to encourage the active participation of all students. Through a longitudinal study of teachers in one school, the conditions for such change were identified and again cast doubt on some of the assumptions behind large-scale attempts at teacher development. Reflecting on these experiences and the evidence they provide, we suggest that teacher development programmes are more likely to be effective where teachers are considered not as individuals subject to training but as agents located in an influential institutional context
Polarized Neutron Matter: A Lowest Order Constrained Variational Approach
In this paper, we calculate some of the polarized neutron matter properties,
using the lowest order constrained variational method with the
potential and employing a microscopic point of view. A comparison is also made
between our results and those of other many-body techniques.Comment: 23 pages, 8 figure
Nonlinear phase mixing and phase-space cascade of entropy in gyrokinetic plasma turbulence
Electrostatic turbulence in weakly collisional, magnetized plasma can be
interpreted as a cascade of entropy in phase space, which is proposed as a
universal mechanism for dissipation of energy in magnetized plasma turbulence.
When the nonlinear decorrelation time at the scale of the thermal Larmor radius
is shorter than the collision time, a broad spectrum of fluctuations at
sub-Larmor scales is numerically found in velocity and position space, with
theoretically predicted scalings. The results are important because they
identify what is probably a universal Kolmogorov-like regime for kinetic
turbulence; and because any physical process that produces fluctuations of the
gyrophase-independent part of the distribution function may, via the entropy
cascade, result in turbulent heating at a rate that increases with the
fluctuation amplitude, but is independent of the collision frequency.Comment: Revtex, 4 pages, 3 figures; replaced to match published versio
Kinetic Simulations of Magnetized Turbulence in Astrophysical Plasmas
This letter presents the first ab initio, fully electromagnetic, kinetic
simulations of magnetized turbulence in a homogeneous, weakly collisional
plasma at the scale of the ion Larmor radius (ion gyroscale). Magnetic and
electric-field energy spectra show a break at the ion gyroscale; the spectral
slopes are consistent with scaling predictions for critically balanced
turbulence of Alfven waves above the ion gyroscale (spectral index -5/3) and of
kinetic Alfven waves below the ion gyroscale (spectral indices of -7/3 for
magnetic and -1/3 for electric fluctuations). This behavior is also
qualitatively consistent with in situ measurements of turbulence in the solar
wind. Our findings support the hypothesis that the frequencies of turbulent
fluctuations in the solar wind remain well below the ion cyclotron frequency
both above and below the ion gyroscale.Comment: 4 pages, 3 figures, submitted to Physical Review Letter
Dissipation-Scale Turbulence in the Solar Wind
We present a cascade model for turbulence in weakly collisional plasmas that
follows the nonlinear cascade of energy from the large scales of driving in the
MHD regime to the small scales of the kinetic Alfven wave regime where the
turbulence is dissipated by kinetic processes. Steady-state solutions of the
model for the slow solar wind yield three conclusions: (1) beyond the observed
break in the magnetic energy spectrum, one expects an exponential cut-off; (2)
the widely held interpretation that this dissipation range obeys power-law
behavior is an artifact of instrumental sensitivity limitations; and, (3) over
the range of parameters relevant to the solar wind, the observed variation of
dissipation range spectral indices from -2 to -4 is naturally explained by the
varying effectiveness of Landau damping, from an undamped prediction of -7/3 to
a strongly damped index around -4.Comment: 6 pages, 2 figures, accepted for publication in AIP Conference
Proceedings on "Turbulence and Nonlinear Processes in Astrophysical Plasmas
Gyrokinetic simulation of entropy cascade in two-dimensional electrostatic turbulence
Two-dimensional electrostatic turbulence in magnetized weakly-collisional
plasmas exhibits a cascade of entropy in phase space [Phys. Rev. Lett. 103,
015003 (2009)]. At scales smaller than the gyroradius, this cascade is
characterized by the dimensionless ratio D of the collision time to the eddy
turnover time measured at the scale of the thermal Larmor radius. When D >> 1,
a broad spectrum of fluctuations at sub-Larmor scales is found in both position
and velocity space. The distribution function develops structure as a function
of v_{perp}, the velocity coordinate perpendicular to the local magnetic field.
The cascade shows a local-scale nonlinear interaction in both position and
velocity spaces, and Kolmogorov's scaling theory can be extended into phase
space.Comment: 8 pages, 10 figures, Conference paper presented at 2009 Asia-Pacific
Plasma Theory Conference. Ver.2 includes corrected typos & updated reference
The age and abundance structure of the stellar populations in the central sub-kpc of the Milky Way
The four main findings about the age and abundance structure of the Milky Way
bulge based on microlensed dwarf and subgiant stars are: (1) a wide metallicity
distribution with distinct peaks at [Fe/H]=-1.09, -0.63, -0.20, +0.12, +0.41;
(2) a high fraction of intermediate-age to young stars where at [Fe/H]>0 more
than 35 % are younger than 8 Gyr, (3) several episodes of significant star
formation in the bulge 3, 6, 8, and 11 Gyr ago; (4) the `knee' in the
alpha-element abundance trends of the sub-solar metallicity bulge appears to be
located at a slightly higher [Fe/H] (about 0.05 to 0.1 dex) than in the local
thick disk.Comment: 4 pages, contributed talk at the IAU Symposium 334 "Rediscovering our
Galaxy" in Potsdam, July 10-14, 201
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