4,167 research outputs found

    Referencing Sources of Molecular Spectroscopic Data in the Era of Data Science: Application to the HITRAN and AMBDAS Databases

    Full text link
    The application described has been designed to create bibliographic entries in large databases with diverse sources automatically, which reduces both the frequency of mistakes and the workload for the administrators. This new system uniquely identifies each reference from its digital object identifier (DOI) and retrieves the corresponding bibliographic information from any of several online services, including the SAO/NASA Astrophysics Data Systems (ADS) and CrossRef APIs. Once parsed into a relational database, the software is able to produce bibliographies in any of several formats, including HTML and BibTeX, for use on websites or printed articles. The application is provided free-of-charge for general use by any scientific database. The power of this application is demonstrated when used to populate reference data for the HITRAN and AMBDAS databases as test cases. HITRAN contains data that is provided by researchers and collaborators throughout the spectroscopic community. These contributors are accredited for their contributions through the bibliography produced alongside the data returned by an online search in HITRAN. Prior to the work presented here, HITRAN and AMBDAS created these bibliographies manually, which is a tedious, time-consuming and error-prone process. The complete code for the new referencing system can be found at \url{https://github.com/hitranonline/refs}.Comment: 11 pages, 5 figures, already published online at https://doi.org/10.3390/atoms802001

    The Velocity Dispersion Profile of the Remote Dwarf Spheroidal Galaxy Leo I: A Tidal Hit and Run?

    Full text link
    (abridged) We present kinematic results for a sample of 387 stars located near Leo I based on spectra obtained with the MMT's Hectochelle spectrograph near the MgI/Mgb lines. We estimate the mean velocity error of our sample to be 2.4 km/s, with a systematic error of < 1 km/s. We produce a final sample of 328 Leo I red giant members, from which we measure a mean heliocentric radial velocity of 282.9 +/- 0.5 km/s, and a mean radial velocity dispersion of 9.2 +/- 0.4 km/s for Leo I. The dispersion profile of Leo I is flat out to beyond its classical `tidal' radius. We fit the profile to a variety of equilibrium dynamical models and can strongly rule out models where mass follows light. Two-component Sersic+NFW models with tangentially anisotropic velocity distributions fit the dispersion profile well, with isotropic models ruled out at a 95% confidence level. The mass and V-band mass-to-light ratio of Leo I estimated from equilibrium models are in the ranges 5-7 x 10^7 M_sun and 9-14 (solar units), respectively, out to 1 kpc from the galaxy center. Leo I members located outside a `break radius' (about 400 arcsec = 500 pc) exhibit significant velocity anisotropy, whereas stars interior appear to have isotropic kinematics. We propose the break radius represents the location of the tidal radius of Leo I at perigalacticon of a highly elliptical orbit. Our scenario can account for the complex star formation history of Leo I, the presence of population segregation within the galaxy, and Leo I's large outward velocity from the Milky Way. The lack of extended tidal arms in Leo I suggests the galaxy has experienced only one perigalactic passage with the Milky Way, implying that Leo I may have been injected into its present orbit by a third body a few Gyr before perigalacticon.Comment: ApJ accepted, 23 figures, access paper as a pdf file at http://www.astro.lsa.umich.edu/~mmateo/research.htm

    Interacting for the environment:Engaging Goffman in pro-environmental action

    Get PDF
    Whilst there are profound disagreements about how more sustainable forms of living might be achieved, most research on pro-environmental action recognises it as a fundamentally social challenge – demanding shifts not merely in individuals’ attitudes and behaviours, but also in social norms, contexts and practices. Despite the social nature of the challenge, perhaps the most fundamental social medium – social interaction - remains under-theorised in this area. To address this gap, this paper applies Erving Goffman’s understandings of social interaction to an ethnographic case study of a pro- environmental change initiative called Environment Champions. The analysis shows that social interaction plays a crucially important role in shaping responses to pro-environmental change processes that has the potential to both help and hinder the spread of pro-environmental action. The paper concludes by exploring how Goffman’s ideas develop and extend current debates about pro- environmental behaviour change

    Promoting EFL learning towards peaceful global citizenship

    Get PDF
    This paper addresses SDG target 4.7 through the lens of Nancy Fraser’s (2008) conceptualisation of parity-of-participation. Her three-pillar conceptualisation includes the equitable distribution of material wealth, egalitarian status among all people, and equal access to representation. This paper attempts to apply her three pillars of participation to the primary classroom which has rarely been attempted before and never in the context of a middle income country. Drawing on interviews, surveys and drawingswith nearly 400 primary-school children in Egypt, we explore how they perceive participation within their classrooms and how participation may influence learning and future life. We conclude by noting that there is an irony in some children’s responses, whereby they display a strong ambition to speak English well, yet believe that they will learn to speak by being passive and silent in the classroom. Other children, however, critique the status quo and suggest more participatory approaches to learning English that will both improve their English mastery and model parity-of-participation in ways that may support their development into adults who strive to live peacefully together as global citizens

    Teachers' classroom feedback: still trying to get it right

    Get PDF
    This article examines feedback traditionally given by teachers in schools. Such feedback tends to focus on children's acquisition and retrieval of externally prescribed knowledge which is then assessed against mandated tests. It suggests that, from a sociocultural learning perspective, feedback directed towards such objectives may limit children's social development. In this article, I draw on observation and interview data gathered from a group of 27 9- to 10-year olds in a UK primary school. These data illustrate the children's perceived need to conform to, rather than negotiate, the teacher's feedback comments. They highlight the children's sense that the teacher's feedback relates to school learning but not to their own interests. The article also includes alternative examples of feedback which draw on children's own inquiries and which relate to the social contexts within which, and for whom, they act. It concludes by suggesting that instead of looking for the right answer to the question of what makes teachers' feedback effective in our current classrooms, a more productive question might be how a negotiation can be opened up among teachers and learners themselves, about how teachers' feedback could support children's learning most appropriately

    Isotopic Dependence of the Casimir Force

    Get PDF
    We calculate the dependence of the Casimir force on the isotopic composition of the interacting objects. This dependence arises from the subtle influence of the nuclear masses on the electronic properties of the bodies. We discuss the relevance of these results to current experiments utilizing the iso-electronic effect to search at very short separations for new weak forces suggested by various unification theories.Comment: 12 pages, Revtex (to appear in Physical Review Letters

    'It's a Form of Freedom': The experiences of people with disabilities within equestrian sport

    Get PDF
    This paper explores the embodied, gendered experiences of disabled horse‐riders. Drawing on data from five in‐depth interviews with paradressage riders, the ways in which their involvement in elite disability sport impacts upon their sense of identity and confidence are explored, as well as the considerable health and social benefits that this involvement brings. Social models of disability are employed and the shortcomings of such models, when applied to disability sport, are highlighted. The data presented here demonstrates the necessity of seeing disability sport as an embodied experience and acknowledging the importance of impairment to the experiences of disabled athletes. Living within an impaired body is also a gendered experience and the implications of this when applied to elite disability sport are considered

    Pre-service teachers’ engagement in a cross-curricular television news project: impact on professional identity

    Get PDF
    This paper focuses on the impact of pre-service teachers’ engagement in the annual BBC News School Report project on their emerging professional identity and on the evidence they provide as part of the process of becoming qualified. The research reported on is drawn from three years of enquiry. Respondents included pre-service teachers themselves, their tutors as representatives of teacher education providers and their mentors as representatives of schools in which they were placed. The methodological approach was interpretative and phenomenological with qualitative and quantitative data being analysed for emergent themes. Two years of evaluations were followed by a third year in which a set of case studies were developed. The research showed that professional identity is enhanced through being in a leading role in respect of curriculum and working with other staff. Through engagement in such projects, this paper moots that preservice teachers develop richer evidence of emerging professionalism as defined by standards of initial teacher training. Moreover, self-perception of role was modified to one in which they saw themselves, and were seen, as equals to qualified staff rather than subservient to or dependent on them. A new more equal power relationship developed as they took on responsibility for the project. Preservice teachers’ move to become full members of the professional community for which they are training was accelerated

    The Metamorphosis of Tidally Stirred Dwarf Galaxies

    Full text link
    We present results from high-resolution N-Body/SPH simulations of rotationally supported dwarf irregular galaxies moving on bound orbits in the massive dark matter halo of the Milky Way.The dwarf models span a range in disk surface density and the masses and sizes of their dark halos are consistent with the predictions of cold dark matter cosmogonies. We show that the strong tidal field of the Milky Way determines severe mass loss in their halos and disks and induces bar and bending instabilities that transform low surface brightness dwarfs (LSBs) into dwarf spheroidals (dSphs) and high surface brightness dwarfs (HSBs) into dwarf ellipticals (dEs) in less than 10 Gyr. The final central velocity dispersions of the remnants are in the range 8-30 km/s and their final v/σv/\sigma falls to values <0.5< 0.5, matching well the kinematics of early-type dwarfs. The transformation requires the orbital time of the dwarf to be \simlt 3-4 Gyr, which implies a halo as massive and extended as predicted by hierarchical models of galaxy formation to explain the origin of even the farthest dSph satellites of the Milky Way, Leo I and Leo II. Only dwarfs with central dark matter densities as high as those of Draco and Ursa Minor can survive for 10 Gyr in the proximity of the Milky Way: this is naturally achieved within hierarchical models, where the densest objects should have small orbital times due to their early formation epochs. Part of the gas is stripped and part is funneled to the center due to the bar, generating one strong burst of star formation in HSBs and smaller, multiple bursts in LSBs. Extended low-surface brightness stellar and gaseous streams originate from LSBs and, when projected along the line of sight, can lead to overestimate the mass-to-light ratio of the bound remnant by a factor \simlt 2,Comment: 29 pages, 34 figures, submitted to ApJ. Figures 5,11 and 32 are given as separate GIF files. Other figures and the movies of the simulations can be found at http://pcblu.mib.infn.it/~lucio/LG/LG.htm

    Surface Screening in the Casimir Force

    Full text link
    We calculate the corrections to the Casimir force between two metals due to the spatial dispersion of their response functions. We employ model-independent expressions for the force in terms of the optical coefficients. We express the non-local corrections to the Fresnel coefficients employing the surface dd_\perp parameter, which accounts for the distribution of the surface screening charge. Within a self-consistent jellium calculation, spatial dispersion increases the Casimir force significatively for small separations. The nonlocal correction has the opposite sign than previously predicted employing hydrodynamic models and assuming abruptly terminated surfaces.Comment: 5 pages, 2 figure
    corecore