25,503 research outputs found
A study of the potential impacts of space utilization
Because the demand for comprehensive impact analysis of space technologies will increase with the use of space shuttles, the academic social sciences/humanities community was surveyed in order to determine their interests in space utilization, to develop a list of current and planned courses, and to generate a preliminary matrix of relevant social sciences. The academic scope/focus of a proposed social science space-related journal was identified including the disciplines which should be represented in the editorial board/reviewer system. The time and funding necessary to develop a self-sustaining journal were assessed. Cost income, general organizational structure, marking/distribution and funding sources were analyzed. Recommendations based on the survey are included
A fourth HI 21-cm absorption system in the sight-line of MG J0414+0534: a record for intervening absorbers
We report the detection of a strong HI 21-cm absorption system at z=0.5344,
as well as a candidate system at z=0.3389, in the sight-line towards the z=2.64
quasar MG J0414+0534. This, in addition to the absorption at the host redshift
and the other two intervening absorbers, takes the total to four (possibly
five). The previous maximum number of 21-cm absorbers detected along a single
sight-line is two and so we suspect that this number of gas-rich absorbers is
in some way related to the very red colour of the background source. Despite
this, no molecular gas (through OH absorption) has yet been detected at any of
the 21-cm redshifts, although, from the population of 21-cm absorbers as a
whole, there is evidence for a weak correlation between the atomic line
strength and the optical--near-infrared colour. In either case, the fact that
so many gas-rich galaxies (likely to be damped Lyman-alpha absorption systems)
have been found along a single sight-line towards a highly obscured source may
have far reaching implications for the population of faint galaxies not
detected in optical surveys, a possibility which could be addressed through
future wide-field absorption line surveys with the Square Kilometre Array.Comment: Accepted by ApJ Letter
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Black and minority ethnic trainees’ experiences of physical education initial teacher training
The official published version can be accessed at the link below.This report draws together the findings of research that aimed to explore black and minority ethnic (BME) trainees’ experiences of Physical Education (PE) initial teacher training (ITT). Although the numbers of BME trainees opting to enter teaching have improved considerably over the last few years, PE remains one of three specific subject areas where they remain significantly under-represented. Current figures suggest that PE attracts approximately 3% of trainees from BME backgrounds, compared with 11% for new entrants into teaching overall. The relative lack of success in attracting BME trainees into PE teaching compared to other subject areas suggests that the subculture of the subject may be a compounding factor. Over the last decade or so, a number of studies have explored the impact of ethnicity on teachers’ professional socialisation and their experiences as teachers in school, but none have focused on experiences within specific subject cultures. The centrality of the body in PE, and the link between this and the perceived low status of the subject, are influencing factors highlighted in the broader literature, including sports studies. For example, research exploring racism and the under-representation of BME participants in sport has highlighted the prevalence of stereotypical attitudes about their physicality and abilities held by coaches, administrators and spectators. Other research has suggested that some minority ethnic groups favour higher status, better paid, careers in areas such as law or medicine rather than teaching. As yet, there has been little attention to ‘race’ and ethnicity within PEITT, although studies have shown the impact of gender on trainees’ developing professional identities, and how teachers’ gendered bodies are important ‘tools’ of their work. In addition, there has been little research that has acknowledged trainees’ multiple identities, or the complex ways in which ‘race’, ethnicity, class and gender and other identity markers intersect to impact on the professional socialisation process. The research on which this report is based sought to fill some of these gaps in our understandings of BME trainees’ experiences of PEITT, and to identify strategies that might help in their recruitment and retention in the longer term. The research was funded through a small Recruitment and Retention Challenge Grant from the Teacher Development Agency (TDA). These grants form part of the TDA’s wider policy agenda to widen the diversity of new intakes opting into teaching. Higher education institutions have been encouraged, through targets and financial support and incentives, to develop specific strategies aimed at widening the diversity of their cohorts. Examples of such strategies include the provision of specialist admission help for BME prospective trainees; opportunities to gain experience in schools; open days and ‘taster’ events; advertising in the ethnic minority media, and the development of good practice guides and staff training to help ITT providers address issues of ‘race’ and ethnicity. 5 The impetus for this research resulted, in part, from presentations and discussions at a one day PEITT Network1 staff seminar on diversity held in October, 2007. The quantitative research conducted by the Association for Physical Education (AfPE) and the Ethnic Minority Foundation (EMF) presented here, showed the extent of the national under-representation of BME students in PEITT. Although the day focused on addressing reasons for BME under representation and strategies that might be used for improving recruitment, we felt it was also important to learn about the qualitative experiences of trainees that have been attracted into PEITT. Understanding the experiences of our current BME trainees might offer useful insights into how we might recruit and retain future such trainees. Our choice of qualitative research was supported by a national study published shortly after the network day, investigating the links between gender, ethnicity and degree attainment (Higher Education Academy, HEA, 2008), which specifically calls for further qualitative studies of students’ experiences of different subject areas.Funding from the Training and Development Agency (TDA
Phosphine Functionalization of GaAs(111)A Surfaces
Phosphorus-functionalized GaAs surfaces have been prepared by exposure of Cl-terminated GaAs(111)A surfaces to triethylphosphine (PEt3) or trichlorophosphine (PCl3), or by the direct functionalization of the native-oxide terminated GaAs(111)A surface with PCl3. The presence of phosphorus on each functionalized surface was confirmed by X-ray photoelectron spectroscopy. High-resolution, soft X-ray photoelectron spectroscopy was used to evaluate the As and Ga 3d regions of such surfaces. On PEt3 treated surfaces, the Ga 3d spectra exhibited a bulk Ga peak as well as peaks that were shifted to 0.35, 0.92 and 1.86 eV higher binding energy. These peaks were assigned to residual Cl-terminated Ga surface sites, surficial Ga2O and surficial Ga2O3, respectively. For PCl3-treated surfaces, the Ga 3d spectra displayed peaks ascribable to bulk Ga(As), Ga2O, and Ga2O3, as well as a peak shifted 0.30 eV to higher binding energy relative to the bulk signal. A peak corresponding to Ga(OH)3, observed on the Cl-terminated surface, was absent from all of the phosphine-functionalized surfaces. After reaction of the Cl-terminated GaAs(111)A surface with PCl3 or PEt3, the As 3d spectral region was free of As oxides and As0. Although native oxide-terminated GaAs surfaces were free of As oxides after reaction with PCl3, such surfaces contained detectable amounts of As0. Photoluminescence measurements indicted that phosphine-functionalized surfaces prepared from Cl-terminated GaAs(111)A surfaces had better electrical properties than the native-oxide capped GaAs(111)A surface, while the native-oxide covered surface treated with PCl3 showed no enhancement in PL intensity
Black and Minority Ethnic Trainees' Experiences of Physical Education Initial Teacher Training: Report to the Training and Development Agency
Remotely controlled mirror of variable geometry for small angle x-ray diffraction with synchrotron radiation
A total-reflecting mirror of 120-cm length was designed and built to focus synchrotron radiation emanating from the electron-positron storage ring at the Stanford Linear Accelerator Center (SPEAR). The reflecting surface is of
unpolished float glass. The bending and tilt mechanism allows very fine control of the curvature and selectability of the critical angle for wavelengths ranging from 0.5 to 3.0 Å. Elliptical curvature is used to minimize aberrations. The mirror is placed asymmetrically onto the ellipse so as to achieve a tenfold demagnification of the source. The bending mechanism reduces nonelastic
deformation (flow) and minimizes strains and stresses in the glass despite its length. Special design features assure stability of the focused image. The mirror
reduces the intensity of shorter wavelength harmonics by a factor of approximately 100
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