Local Column Density Distribution Function from HI selected galaxies

The cross-section of sky occupied by a particular neutral hydrogen column density provides insight into the nature of Lyman-alpha absorption systems. We have measured this column density distribution at z=0 using 21-cm HI emission from a blind survey. A subsample of HI Parkes All Sky Survey (HIPASS) galaxies have been imaged with the Australia Telescope Compact Array (ATCA). The contribution of low HI mass galaxies 10^7.5 to 10^8 M_solar is compared to that of M_star (10^10 to 10^10.5 M_solar) galaxies. We find that the column density distribution function is dominated by low HI mass galaxies with column densities in the range 3x10^18 to 2x10^20 cm^-2. This result is not intuitively obvious. M_star galaxies may contain the bulk of the HI gas, but the cross-section presented by low HI mass galaxies 10^7.5 to 10^8 M_solar is greater at moderate column densities. This result implies that moderate column density Lyman-alpha absorption systems may be caused by a range of galaxy types and not just large spiral galaxies as originally thought.Comment: 5 pages, including 1 figure. To appear in "Extragalactic Gas at Low Redshift" (ASP Conf. Series, Weymann Conf.

The Column Density Distribution Function at z=0 from HI Selected Galaxies

We have measured the column density distribution function, f(N), at z=0 using 21-cm HI emission from galaxies selected from a blind HI survey. f(N) is found to be smaller and flatter at z=0 than indicated by high-redshift measurements of Damped Lyman-alpha (DLA) systems, consistent with the predictions of hierarchical galaxy formation. The derived DLA number density per unit redshift, dn/dz =0.058, is in moderate agreement with values calculated from low-redshift QSO absorption line studies. We use two different methods to determine the types of galaxies which contribute most to the DLA cross-section: comparing the power law slope of f(N) to theoretical predictions and analysing contributions to dn/dz. We find that comparison of the power law slope cannot rule out spiral discs as the dominant galaxy type responsible for DLA systems. Analysis of dn/dz however, is much more discriminating. We find that galaxies with log M_HI < 9.0 make up 34% of dn/dz; Irregular and Magellanic types contribute 25%; galaxies with surface brightness > 24 mag arcsec^{-2} account for 22% and sub-L* galaxies contribute 45% to dn/dz. We conclude that a large range of galaxy types give rise to DLA systems, not just large spiral galaxies as previously speculated.Comment: 13 pages, low resolution figures in the appendix, MNRAS accepte

Evolution of damped Lyman alpha kinematics and the effect of spatial resolution on 21-cm measurements

We have investigated the effect of spatial resolution on determining pencil-beam like velocity widths and column densities in galaxies. Three 21-cm datasets are used, the HIPASS galaxy catalogue, a subset of HIPASS galaxies with ATCA maps and a high-resolution image of the LMC. Velocity widths measured from 21-cm emission in local galaxies are compared with those measured in intermediate redshift Damped Lyman alpha (DLA) absorbers. We conclude that spatial resolution has a severe effect on measuring pencil-beam like velocity widths in galaxies. Spatial smoothing by a factor of 240 is shown to increase the median velocity width by a factor of two. Thus any difference between velocity widths measured from global profiles or low spatial resolution 21-cm maps at z=0 and DLAs at z>1 cannot unambiguously be attributed to galaxy evolution. The effect on column density measurements is less severe and the values of dN/dz from local low-resolution 21-cm measurements are expected to be overestimated by only ~10 per cent.Comment: 5 pages, 6 figures, accepted for publication in MNRAS letter

The limits and powers of the technological text

This thesis examines the implications for text and subject of the digital technology of hypertext. Focussing on the printed texts of Alasdair Gray, it explores the complex relationship between humans and technology depicted in his fictions. Gray’s fictional examples provide the basis for a wider discussion regarding the impact of technology upon the lives of the subjects who engage with it and in particular who engages with the technologies of writing. It aims to illustrate how digital technologies of writing can be considered in light of some of the textual concerns raised by fiction and criticism in the late age of print, notably issues of narrative theory and the cultural function of linear stories and histories. Straining in many respects against the limitations of the printed form, Gray’s boundary-pushing texts, whilst remaining firmly rooted in the aesthetic tradition of the book as object, perhaps anticipate a more flexible textual form. The digital space of hypertext can be seen to offer a new arena for the textual debate, but does it live up to the claims of some of its critics, particularly in terms of its rapport with aspects of contemporary theory? And what may be the consequences of text dematerialised in the digital medium? As well as considering the textual possibilities of hypertext, the thesis also looks at the ways in which subjects relate to technology as well as those by which technology – and particularly writing technology – relates to them. Given the ambiguous role of technology in the life of the subject – employed on the one hand as part of a project and promise of rational enlightenment through science and on the other as a military and ideological means of repression – the consequences of technological development and of the digital revolution for the written word must be closely considered. Finally, the thesis questions the types of texts that may be constructed through an engagement with the digital technology of hypertext and what types of subjects these in turn might construct

The State of Out-of-School Girls in Sierra Leone: Findings Across Six Districts - Executive Summary

The Girls' Circles baseline survey affirmed what we know – that girls' lives in Sierra Leone, especially those who are out of school, are characterised by multiple hardships: little to no education; the ubiquity of transactional sex; teen pregnancy; and everyday violence. Whilst little of this will be new for those who know Sierra Leone, the scale of these issues (which are likely to be under reported) is shocking, as is their everyday nature – girls struggling, for example, to identify violence where it is simply part of the fabric of their daily lives.This report was born out of a recognition that all of this rich data is available and should be shared with the world, particularly given the relative rarity of girls' voices being foregrounded in the Sierra Leonean context. It presents an opportunity for a 'state of the nation' summary about the lives of girls who are often most marginalised in Sierra Leone, and the findings are grounded in what girls themselves and their mentors are telling us about their lives.The availability of this nuanced data and verbatim accounts has enabled the report to go beyond the simplified or binary narratives often presented about girls, to present the realities of their lives, in their words. We hope this provides deep insight into their experiences and what lies behind these, as well as the possibilities for positive change

The State of Out-of-School Girls in Sierra Leone: Findings Across Six Districts

The Girls' Circles baseline survey affirmed what we know – that girls' lives in Sierra Leone, especially those who are out of school, are characterised by multiple hardships: little to no education; the ubiquity of transactional sex; teen pregnancy; and everyday violence. Whilst little of this will be new for those who know Sierra Leone, the scale of these issues (which are likely to be under reported) is shocking, as is their everyday nature – girls struggling, for example, to identify violence where it is simply part of the fabric of their daily lives.This report was born out of a recognition that all of this rich data is available and should be shared with the world, particularly given the relative rarity of girls' voices being foregrounded in the Sierra Leonean context. It presents an opportunity for a 'state of the nation' summary about the lives of girls who are often most marginalised in Sierra Leone, and the findings are grounded in what girls themselves and their mentors are telling us about their lives.The availability of this nuanced data and verbatim accounts has enabled the report to go beyond the simplified or binary narratives often presented about girls, to present the realities of their lives, in their words. We hope this provides deep insight into their experiences and what lies behind these, as well as the possibilities for positive change

Preschool and School Meal Policies: An Overview of What We Know about Regulation, Implementation, and Impact on Diet in the UK, Sweden, and Australia

School meals make significant contributions to healthy dietary behaviour, at a time when eating habits and food preferences are being formed. We provide an overview of the approaches to the provision, regulation, and improvement of preschool and primary school meals in the UK, Sweden, and Australia, three countries which vary in their degree of centralisation and regulation of school meals. Sweden has a centralised approach; all children receive free meals, and a pedagogical approach to meals is encouraged. Legislation demands that meals are nutritious. The UK system is varied and decentralised. Meals in most primary schools are regulated by food-based standards, but preschool-specific meal standards only exist in Scotland. The UK uses food groups (starchy foods, fruit and vegetables, proteins and dairy) in a healthy plate approach. Australian States and Territories all employ guidelines for school canteen food, predominantly using a “traffic light” approach outlining recommended and discouraged foods; however, most children bring food from home and are not covered by this guidance. The preschool standards state that food provided should be nutritious. We find that action is often lacking in the preschool years, and suggest that consistent policies, strong incentives for compliance, systematic monitoring, and an acknowledgement of the broader school eating environment (including home provided food) would be beneficial

Comparison of culture based methods for the isolation of Clostridium difficile from stool samples in a research setting

AbstractEffective isolation of Clostridium difficile from stool samples is important in the research setting, especially where low numbers of spores/vegetative cells may be present within a sample. In this study, three protocols for stool culture were investigated to find a sensitive, cost effective and timely method of C. difficile isolation. For the initial enrichment step, the effectiveness of two different rich media, cycloserine-cefoxitin fructose broth (CCFB) and cycloserine-cefoxitin mannitol broth with taurocholate and lysozyme (CCMB-TAL) were compared. For the comparison of four different, selective solid media; Cycloserine-cefoxitin fructose agar (CCFA), Cycloserine-cefoxitin egg yolk agar (CCEY), ChromID C. difficile and tryptone soy agar (TSA) with 5% sheep's blood with and without preceding broth enrichment were used. As a means to enable differentiation between C. difficile and other fecal flora, the effectiveness of the inclusion of a pH indictor (1% Neutral Red), was also evaluated. The data derived indicated that CCFB is more sensitive than CCMB-TAL, however, the latter had an improved recovery rate. A broth enrichment step had a reduced sensitivity over direct plating. ChromID C. difficile showed the best recovery rate whereas CCEY egg yolk agar was the most sensitive of the four. The addition of 1% Neutral Red did not show sufficient colour change when added to CCEY egg yolk agar to be used as a differential medium. For a low cost, timely and sensitive method of isolating C. difficile from stool samples we recommend direct plating onto CCEY egg yolk agar after heat shock

Alternative Journalism as Monitorial Citizenship? A case study of a local news blog

Recent years have seen claims that some examples of online alternative journalism in the form of hyperlocal and local blogs are helping to address society’s “democratic deficit” by subjecting the actions of the powerful to increased public scrutiny, in a process that has been described as “monitorial citizenship”. To explore how this might work in practice, this study examines the origins, motivations and practices of one such site in the United Kingdom: the Leeds Citizen. The aim is to provide the sort of detailed consideration in depth that is almost by definition missing from wider surveys of the field. To this end, the case study is based on a series of interviews with the site’s creator, augmented by analysis of content, all discussed within the context of scholarly literature on how alternative, non-commercial forms of journalism operate in the digital age. The article concludes that this contemporary form of alternative journalism may indeed be described as an example of monitorial citizenship in action, but there is also a need for further research

The HIPASS Catalogue - II. Completeness, Reliability, and Parameter Accuracy

The HI Parkes All Sky Survey (HIPASS) is a blind extragalactic HI 21-cm emission line survey covering the whole southern sky from declination -90 to +25. The HIPASS catalogue (HICAT), containing 4315 HI-selected galaxies from the region south of declination +2, is presented in Meyer et al. (2004a, Paper I). This paper describes in detail the completeness and reliability of HICAT, which are calculated from the recovery rate of synthetic sources and follow-up observations, respectively. HICAT is found to be 99 per cent complete at a peak flux of 84 mJy and an integrated flux of 9.4 Jy km/s. The overall reliability is 95 per cent, but rises to 99 per cent for sources with peak fluxes >58 mJy or integrated flux > 8.2 Jy km/s. Expressions are derived for the uncertainties on the most important HICAT parameters: peak flux, integrated flux, velocity width, and recessional velocity. The errors on HICAT parameters are dominated by the noise in the HIPASS data, rather than by the parametrization procedure.Comment: Accepted for publication in MNRAS. 12 pages, 11 figures. Paper with higher resolution figures can be downloaded from http://hipass.aus-vo.or