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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
Resolving the structure of TiBe
There has been considerable controversy regarding the structure of
TiBe, which is variously reported as hexagonal and tetragonal. Lattice
dynamics simulations based on density functional theory show the tetragonal
phase space group to be more stable over all temperatures, while the
hexagonal phase exhibits an imaginary phonon mode, which, if followed, would
lead to the cell adopting the tetragonal structure. We then report the
predicted ground state elastic constants and temperature dependence of the bulk
modulus and thermal expansion for the tetragonal phase.Comment: In press at Acta Crystallographica B. Supplementary material appende
Evidence for Black Hole Growth in Local Analogs to Lyman Break Galaxies
We have used XMM-Newton to observe six Lyman Break Analogs (LBAs): members of
the rare population of local galaxies that have properties that are very
similar to distant Lyman Break Galaxies. Our six targets were specifically
selected because they have optical emission-line properties that are
intermediate between starbursts and Type 2 (obscured) AGN. Our new X-ray data
provide an important diagnostic of the presence of an AGN. We find X-ray
luminosities of order 10^{42} erg/s and ratios of X-ray to far-IR luminosities
that are higher than values in pure starburst galaxies by factors ranging from
~ 3 to 30. This strongly suggests the presence of an AGN in at least some of
the galaxies. The ratios of the luminosities of the hard (2-10 keV) X-ray to [O
III]\lambda 5007 emission-line are low by about an order-of-magnitude compared
to Type 1 AGN, but are consistent with the broad range seen in Type 2 AGN.
Either the AGN hard X-rays are significantly obscured or the [O III] emission
is dominated by the starburst. We searched for an iron emission line at ~ 6.4
keV, which is a key feature of obscured AGN, but only detected emission at the
~ 2\sigma level. Finally, we find that the ratios of the mid-infrared (24\mu m)
continuum to [O III]\lambda 5007 luminosities in these LBAs are higher than the
values for Type 2 AGN by an average of 0.8 dex. Combining all these clues, we
conclude that an AGN is likely to be present, but that the bolometric
luminosity is produced primarily by an intense starburst. If these black holes
are radiating at the Eddington limit, their masses would lie in the range of
10^5 to 10^6 M_{sun}. These objects may offer ideal local laboratories to
investigate the processes by which black holes grew in the early universe.Comment: Accepted for publication in Ap
Effects of Gallium Doping in Garnet-Type Li7La3Zr2O12 Solid Electrolytes
Garnet-type Li7La3Zr2O12 (LLZrO) is a candidate solid electrolyte material that is now being intensively optimized for application in commercially competitive solid state Li+ ion batteries. In this study we investigate, by force-field-based simulations, the effects of Ga3+ doping in LLZrO. We confirm the stabilizing effect of Ga3+ on the cubic phase. We also determine that Ga3+ addition does not lead to any appreciable structural distortion. Li site connectivity is not significantly deteriorated by the Ga3+ addition (>90% connectivity retained up to x = 0.30 in Li7–3xGaxLa3Zr2O12). Interestingly, two compositional regions are predicted for bulk Li+ ion conductivity in the cubic phase: (i) a decreasing trend for 0 ≤ x ≤ 0.10 and (ii) a relatively flat trend for 0.10 < x ≤ 0.30. This conductivity behavior is explained by combining analyses using percolation theory, van Hove space time correlation, the radial distribution function, and trajectory density
A Chandra observation of the ultraluminous infrared galaxy IRAS 19254--7245 (the Superantennae): X-ray emission from the Compton-thick AGN and the diffuse starburst
We present a {\it Chandra} observation of IRAS 19254--7245, a nearby ULIRG
also known as {\it the Superantennae}. The high spatial resolution of {\it
Chandra} allows us to disentangle for the first time the diffuse starburst
emission from the embedded Compton-thick AGN. The 2-10 keV spectrum of the AGN
emission is fitted by a flat power-law ) and a He-like Fe K
line with EW1.5 keV, consistent with previous observations. The Fe
K line profile could be resolved as a blend of a neutral 6.4 keV line
and an ionized 6.7 keV (He-like) or 6.9 keV (H-like) line. Variability is
detected compared with the previous {\it XMM-Newton} and {\it suzaku}
observations, demonstrating the compact size of the iron line emission. We fit
the spectrum of the galaxy-scale extended emission excluding the AGN and other
bright point sources with a soft thermal component with kT~0.8 keV. The
luminosity of the extended emission is about one order of magnitude lower than
that of the AGN. The basic physical and structural properties of the extended
emission are fully consistent with a galactic wind being driven by the
starburst (no contribution to the feedback by the AGN is required). A candidate
ultra-luminous X-ray source is detected 8\arcsec\ south of the southern
nucleus. The 0.3-10 keV luminosity of this off-nuclear point source is
~ erg s if the emission is isotropic and the source is
associated with the Superantennae.Comment: 31 pages, 10 figures, submitted to Ap
Hydrogen solubility in zirconium intermetallic second phase particles
The enthalpies of solution of H in Zr binary intermetallic compounds formed
with Cu, Cr, Fe, Mo, Ni, Nb, Sn and V were calculated by means of density
functional theory simulations and compared to that of H in {\alpha}-Zr. It is
predicted that all Zr-rich phases (formed with Cu, Fe, Ni and Sn), and those
phases formed with Nb and V, offer lower energy, more stable sites for H than
{\alpha}-Zr. Conversely, Mo and Cr containing phases do not provide
preferential solution sites for H. In all cases the most stable site for H are
those that offer the highest coordination fraction of Zr atoms. Often these are
four Zr tetrahedra but not always. Implications with respect to H-trapping
properties of commonly observed ternary phases such as Zr(Cr,Fe)2, Zr2(Fe,Ni)
and Zr(Nb,Fe)2 are also discussed.Comment: manuscript accepted for publication in Journal of Nuclear Materials
(2013
Enhancing efficiency of single, large-aperture antennas
Numerical analysis method provides means of describing energy distribution in focal plane of parabolic surface in terms of phase and wavelength. Two approaches for enhancing antenna efficiency include single, large reflector focused to feeding element, and array of smaller apertures whose individual outputs are summed
Ethnic identity and aspirations among rural Alaska youth
The villages of rural Alaska comprise one of the most exceptional, yet least visible, sociocultural environments in the United States They are geographically remote, and set off from the mainstream also by their unique Eskimo, Indian or Aleut cultures. At the same time many economic, legal and cultural connections pull these villages toward the dominant U.S. society, impelling continual and rapid social change. Our research focuses on adolescents growing up in this culturally complex and changing environment. We employ survey data from adolescents in 19 rural schools to explore relationships between ethnic identity and students\u27 expectations about moving away or attending college. Many students describe their ethnic identity as mixed, both Native and non-Native. On some key variables, the responses of mixed-identity students fall between those of Natives and non-Natives, supporting a theoretical conception of ethnicity as a matter of degree rather than category. Migration and college expectations vary with ethnic identity, but the college expectations/identity relationship fades when we adjust for other variables. Ethnicity affects expectations for the most part indirectly, through “cultural tool kit” variables including family role models and support. Gender differences in expectations, on the other hand, remain substantial even after adjusting for other variables
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