A Group of Red, Ly-alpha Emitting, High Redshift Galaxies

We have discovered two new high redshift (z=2.38) galaxies, near the previously known z=2.38 galaxy 2139-4434 B1 (Francis et al. 1996). All three galaxies are strong Ly-alpha emitters, and have much redder continuum colors (I-K about 5) than other optically-selected high redshift galaxies. We hypothesize that these three galaxies are QSO IIs; radio-quiet counterparts of high redshift radio galaxies, containing concealed QSO nuclei. The red colors are most easily modelled by an old (> 0.5 Gyr), massive (> 10E11 solar masses) stellar population. If true, this implies that at least one galaxy cluster of mass much greater than 3E11 solar masses had collapsed before redshift five.Comment: 12 pages, 2 figures, uses aaspp4 style file. Accepted for publication in Astrophysical Journal Letter

Does ethnicity, gender or age of physiotherapy students affect performance in the final clinical placements? An exploratory study

This is the post-print version of the final paper published in Physiotherapy. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2013 Elsevier B.V.Objectives - To explore demographic differences in awarded marks of the final clinical placement in a physiotherapy undergraduate programme. Design - Retrospective analysis of clinical placement assessment marks. Setting - A London university offering clinical placements throughout South East England. Participants - 333 physiotherapy students entering physiotherapy training between 2005 to 2009. Main outcome measures Marks awarded following assessment using a clinical placement assessment form. Results - The mean mark (SD) for age were standard entry 71 (7.4) vs. mature entry 72 (7.99) (ns); for gender male 72 (8.45) vs. female 71 (7.21) (ns); and ethnicity White British 72 (7.71) vs. ethnic minority 70 (7.01) (p = 0.023). No interaction effects were observed between the independent variables and only ethnicity demonstrated a statistically significant effect (mean difference (MD) 2.4% 95%CI 0.5 to 4.3, F = 5.24, p = 0.023). This difference was maintained in most subcategories. Significant differences were observed for the interpersonal section (MD 2.21% 95%CI 0.14 to 4.28, F = 4.409, p = 0.03), the clinical reasoning section (MD 2.39% 95%CI 0.53 to 4.25, F = 6.37, p = 0.012) and the treatment section (MD 2.93 95%CI 1.10 to 4.83, F = 9.198, p = 0.003). Conclusions - Physiotherapy students from minority ethnic backgrounds were awarded a significantly lower mark than their white majority peers in final clinical placements, although the difference was small. Potential reasons are considered, with the strongest recommendation being for further enquiry into the potential relationship between ethnicity and success in undergraduate physiotherapy education

An Optical/Near-Infrared Study of Radio-Loud Quasar Environments II. Imaging Results

We use optical and near-IR imaging to examine the properties of the significant excess population of K>=19 galaxies found in the fields of 31 z=1-2 radio-loud quasars by Hall, Green & Cohen (1998). The excess occurs on two spatial scales: a component at <40'' from the quasars significant compared to the galaxy surface density at >40'' in the same fields, and a component roughly uniform to ~100'' significant compared to the galaxy surface density seen in random-field surveys in the literature. The r-K color distributions of the excess galaxy populations are indistinguishable and are significantly redder than the color distribution of the field population. The excess galaxies are consistent with being predominantly early-type galaxies at the quasar redshifts, and there is no evidence that they are associated with intervening MgII absorption systems. The average excess within 0.5 Mpc (~65'') of the quasars corresponds to Abell richness class ~0 compared to the galaxy surface density at >0.5 Mpc from the quasars, and to Abell richness class ~1.5 compared to that from the literature. We discuss the spectral energy distributions (SEDs) of galaxies in fields with data in several passbands. Most candidate quasar-associated galaxies are consistent with being 2-3 Gyr old early-types at the quasar redshifts of z~1.5. However, some objects have SEDs consistent with being 4-5 Gyr old at z~1.5, and a number of others are consistent with ~2 Gyr old but dust-reddened galaxies at the quasar redshifts. These potentially different galaxy types suggest there may be considerable dispersion in the properties of early-type cluster galaxies at z~1.5. There is also a population of galaxies whose SEDs are best modelled by background galaxies at z>2.5.Comment: Accepted to ApJ; 54 pages including 30 figures; 2 color GIF files available separately; also available from http://www.astro.utoronto.ca/~hall/thesis.htm

Second-Generation Objects in the Universe: Radiative Cooling and Collapse of Halos with Virial Temperatures Above 10^4 Kelvin

The first generation of protogalaxies likely formed out of primordial gas via H2-cooling in cosmological minihalos with virial temperatures of a few 1000K. However, their abundance is likely to have been severely limited by feedback processes which suppressed H2 formation. The formation of the protogalaxies responsible for reionization and metal-enrichment of the intergalactic medium, then had to await the collapse of larger halos. Here we investigate the radiative cooling and collapse of gas in halos with virial temperatures Tvir > 10^4K. In these halos, efficient atomic line radiation allows rapid cooling of the gas to 8000 K; subsequently the gas can contract nearly isothermally at this temperature. Without an additional coolant, the gas would likely settle into a locally gravitationally stable disk; only disks with unusually low spin would be unstable. However, we find that the initial atomic line cooling leaves a large, out-of-equilibrium residual free electron fraction. This allows the molecular fraction to build up to a universal value of about x(H2) = 10^-3, almost independently of initial density and temperature. We show that this is a non--equilibrium freezeout value that can be understood in terms of timescale arguments. Furthermore, unlike in less massive halos, H2 formation is largely impervious to feedback from external UV fields, due to the high initial densities achieved by atomic cooling. The H2 molecules cool the gas further to about 100K, and allow the gas to fragment on scales of a few 100 Msun. We investigate the importance of various feedback effects such as H2-photodissociation from internal UV fields and radiation pressure due to Ly-alpha photon trapping, which are likely to regulate the efficiency of star formation.Comment: Revised version accepted by ApJ; some reorganization for clarit

Songs, Sounds and Sentiments in Translation:The Transnational Travels of Corsican and Georgian Polyphony

This article considers the concept of translation as applied to the phenomenon of amateur singers in the West learning songs from ‘other’ cultures. Following an examination of the reasons why some people may prefer to sing in a language that is not their mother tongue, I go on to explore the processes involved in learning a new musical language, taking as my case study traditional polyphonic songs from Corsica and Georgia. I consider the roles of the native practitioner as teacher and transmitter and the non-native teacher as transmitter and intermediary, examining the methods developed by particular teachers to help students reach a deeper cultural understanding while also finding an ‘authentic’ sound. Pursuing the notion of social relations being implicit in the acts of both translation and music making, I conclude by reflecting on the kinds of transformations—personal and political, as well as musical—that may result

Polyphony as Tool and Trope: Theorising the Work of Polyphony in the Twenty-First Century

This paper offers a theoretical analysis of polyphonic singing as a form of social and intercultural engagement, a tool for building social capital, and a site for exploring new subjectivities. Building on arguments presented in my new book, A Different Voice, A Different Song, and with particular reference to those who sing songs from ‘other’ cultures, I consider a set of related issues, including the politics of participation, the transformative potential of performance, and questions of authenticity and identity. In the process, I enter into dialogue with recent theoretical work in ethnomusicology, social anthropology, political science and cultural theory. In providing alternatives to the trope of music as commodity that is more usually associated with the world music industry, this approach will hopefully shed a different kind of light on questions about what is lost or gained in the changing polyphonic landscape of the 21st century

Anchors and Sails: Music and Culture Contact in Corsica

The chapter explores the extent to which Corsica's pivotal position in the Mediterranean has affected the development of indigenous musical styles and practices. I begin with a brief examination of the types of influences and affinities that have been postulated for Corsica’s musical evolution. It is only in the island’s more recent history, however, that it is possible to document with a surer confidence instances of direct intercultural contact on a specifically musical plane and it is to an exploration of some of the most recent cases that I turn my attention in the second half of the chapter. In the course of this discussion with its more global frame of reference, I aim to offer an insight into the motivations behind contacts that have been actively courted and the implications of both literal contacts and perceived affinities at both a practical and a politico-philosophical level. Finally I refocus on the question of 'Mediterranean' music as I examine the impulse on the part of contemporary Corsican musicians to explore the specifically Mediterranean roots of their island’s music and, in some cases, to forge links with musics and musicians from other Mediterranean traditions based on a perception of shared heritage

The Past in Music: Introduction

In this article (which also acts as an introduction to a selection of case studies on the theme 'the past in music') I offer a few thoughts on the nature of the past and the role of memory in constructing historical narrative, with reference to the way in which these concepts have been theorised by historians, archaeologists, anthropologists and ethnomusicologists. In reviewing the different ways in which echoes of the past can still be heard in the music of the present, I consider the capacity of music to evoke, embody and transform the past and, by so doing, to act as a medium for history and its interpretation