7,566 research outputs found
Partisan, scholarly and active: for an organic public sociology of work and the case of critical labour studies
Despite a thriving tradition of critical scholarship in UK-based sociology of work, Burawoy’s call for a partisan organic public sociology that is part of ‘a social movement beyond the academy’ and Bourdieu’s plea for committed scholarship in the service of the social movement against neo-liberalism have received scant attention. This article seeks to stimulate debate by presenting a framework for a left-radical organic public sociology of work based on Gramsci’s concept of the connected organic intellectual rather than Bourdieu’s expert committed scholar. The latter, it is argued, is incompatible with activist partisan scholarship based on democratised relations between researchers and researched. Participatory Action Research is offered as a methodological orientation that underpins and enables organic scholars of work to engage actively with the marginalised and labour in the co-creation of knowledge that aids their struggles for change
Biocidal silver and silver/titania composite films grown by chemical vapour deposition
This paper describes the growth and testing of highly active biocidal films based on photocatalytically active films of TiO2, grownby
thermal CVD, functionally and structurallymodified by deposition of nanostructured silver via a novel flame assisted combination
CVD process. The resulting composite films are shown to be highly durable, highly photocatalytically active and are also shown to
possess strong antibacterial behaviour. The deposition control, arising from the described approach, offers the potential to control
the film nanostructure, which is proposed to be crucial in determining the photo and bioactivity of the combined film structure,
and the transparency of the composite films. Furthermore, we show that the resultant films are active to a range of organisms,
including Gram-negative and Gram-positive bacteria, and viruses. The very high-biocidal activity is above that expected from the
concentrations of silver present, and this is discussed in terms of nanostructure of the titania/silver surface. These properties are
especially significant when combined with the well-known durability of CVD deposited thin films, offering new opportunities for
enhanced application in areas where biocidal surface functionality is sought
Highly bioactive silver and silver/titania composite films grown by chemical vapour deposition
This paper describes how photocatalytically active films of TiO2, grown by thermal CVD, may be functionally and structurally modified by deposition of nano-structured silver via a novel flame assisted CVD process. The resulting composite films are shown to be highly durable, highly photocatalytically active and are also shown to possess strong antibacterial behaviour.
The deposition control, arising from the described approach, offers the potential to control the film nanostructure, which is proposed to be crucial in determining the photo and bio-activity of the combined film structure, and the transparency of the composite films.
Furthermore, we show that the resultant films also exhibit “self-regeneration” capability, in that they both kill bacteria present on the film surface and then photo-degrade the residues. Such a dual action significantly reducing the problems of surface deactivation due to build up of contamination.
These properties are especially significant when combined with the well-known durability of CVD deposited thin films, offering new opportunities for enhanced application in areas where bioactive surface functionality is sought
Galactic Halo Stars in Phase Space :A Hint of Satellite Accretion?
The present day chemical and dynamical properties of the Milky Way bear the
imprint of the Galaxy's formation and evolutionary history. One of the most
enduring and critical debates surrounding Galactic evolution is that regarding
the competition between ``satellite accretion'' and ``monolithic collapse'';
the apparent strong correlation between orbital eccentricity and metallicity of
halo stars was originally used as supporting evidence for the latter. While
modern-day unbiased samples no longer support the claims for a significant
correlation, recent evidence has been presented by Chiba & Beers
(2000,AJ,119,2843) for the existence of a minor population of high-eccentricity
metal-deficient halo stars. It has been suggested that these stars represent
the signature of a rapid (if minor) collapse phase in the Galaxy's history.
Employing velocity- and integrals of motion-phase space projections of these
stars, coupled with a series of N-body/Smoothed Particle Hydrodynamic (SPH)
chemodynamical simulations, we suggest an alternative mechanism for creating
such stars may be the recent accretion of a polar orbit dwarf galaxy.Comment: 12 pages(incl. figures). Accepted for publication in ApJ letters
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Diagnosis of Helicobacter pylori by carbon-13 urea breath test using a portable mass spectrometer
CONTEXT: In the non-invasive detection of markers of disease, mass spectrometry is able to detect small quantities of volatile markers in exhaled air. However, the problem of size, expense and immobility of conventional mass spectrometry equipment has restricted its use. Now, a smaller, less expensive, portable quadrupole mass spectrometer system has been developed. Helicobacter pylori has been implicated in the development of chronic gastritis, gastric and duodenal ulcers and gastric cancer. OBJECTIVES: To compare the results obtained from the presence of H. pylori by a carbon-13 urea test using a portable quadrupole mass spectrometer system with those from a fixed mass spectrometer in a hospital-based clinical trial. METHODS: Following ethical approval, 45 patients attending a gastroenterology clinic at the Royal Liverpool University Hospital exhaled a breath sample into a Tedlar gas sampling bag. They then drank an orange juice containing urea radiolabelled with carbon and 30 min later gave a second breath sample. The carbon-13 content of both samples was measured using both quadrupole mass spectrometer systems. If the post-drink level exceeded the pre-drink level by 3% or more, a positive diagnosis for the presence of H. pylori was made. RESULTS: The findings were compared to the results using conventional isotope ratio mass spectrometry using a laboratory-based magnetic sector instrument off-site. The results showed agreement in 39 of the 45 patients. CONCLUSIONS: This study suggests that a portable quadrupole mass spectrometer is a potential alternative to the conventional centralised testing equipment. Future development of the portable quadrupole mass spectrometer to reduce further its size and cost is indicated, together with further work to validate this new equipment and to enhance its use in mass spectrometry diagnosis of other medical conditions
Reconstruction and paleoclimatic significance of late Quaternary glaciers in the Tararua Range, North Island, New Zealand
Reactive Inkjet Printing of Regenerated Silk Fibroin Films for Use as Dental Barrier Membranes
Current commercially available barrier membranes for oral surgery have yet to achieve a perfect design. Existing materials used are either non-resorbable and require a second surgery for their extraction, or alternatively are resorbable but suffer from poor structural integrity or degrade into acidic by-products. Silk has the potential to overcome these issues and has yet to be made into a commercially available dental barrier membrane. Reactive inkjet printing (RIJ) has recently been demonstrated to be a suitable method for assembling silk in its regenerated silk fibroin (RSF) form into different constructs. This paper will establish the properties of RSF solutions for RIJ and the suitability of RIJ for the construction of RSF barrier membranes. Printed RSF films were characterised by their crystallinity and surface properties, which were shown to be controllable via RIJ. RSF films degraded in either phosphate buffered saline or protease XIV solutions had degradation rates related to RSF crystallinity. RSF films were also printed with the inclusion of nano-hydroxyapatite (nHA). As reactive inkjet printing could control RSF crystallinity and hence its degradation rate, as well as offering the ability to incorporate bioactive nHA inclusions, reactive inkjet printing is deemed a suitable alternative method for RSF processing and the production of dental barrier membranes
The role of feedback in shaping the structure of the interstellar medium
We present an analysis of the role of feedback in shaping the neutral hydrogen (H I) content of simulated disc galaxies. For our analysis, we have used two realizations of two separate Milky Way-like (similar to L star) discs - one employing a conservative feedback scheme (McMaster Unbiased Galaxy Survey), the other significantly more energetic [Making Galaxies In a Cosmological Context (MaGICC)]. To quantify the impact of these schemes, we generate zeroth moment (surface density) maps of the inferred H I distribution; construct power spectra associated with the underlying structure of the simulated cold interstellar medium, in addition to their radial surface density and velocity dispersion profiles. Our results are compared with a parallel, self-consistent, analysis of empirical data from The H I Nearby Galaxy Survey (THINGS). Single power-law fits (P proportional to k(gamma)) to the power spectra of the stronger feedback (MaGICC) runs (over spatial scales corresponding to similar to 0.5 to similar to 20 kpc) result in slopes consistent with those seen in the THINGS sample (gamma similar to -2.5). The weaker feedback (MUGS) runs exhibit shallower power-law slopes (gamma similar to -1.2). The power spectra of the MaGICC simulations are more consistent though with a two-component fit, with a flatter distribution of power on larger scales (i.e. gamma similar to -1.4 for scales in excess of similar to 2 kpc) and a steeper slope on scales below similar to 1 kpc (gamma similar to -5), qualitatively consistent with empirical claims, as well as our earlier work on dwarf discs. The radial H I surface density profiles of the MaGICC discs show a clear exponential behaviour, while those of the MUGS suite are essentially flat; both behaviours are encountered in nature, although the THINGS sample is more consistent with our stronger (MaGICC) feedback runs
MaGICC-WDM: the effects of warm dark matter in hydrodynamical simulations of disc galaxy formation
We study the effect of warm dark matter (WDM) on hydrodynamic simulations of
galaxy formation as part of the Making Galaxies in a Cosmological Context
(MaGICC) project. We simulate three different galaxies using three WDM
candidates of 1, 2 and 5 keV and compare results with pure cold dark matter
simulations. WDM slightly reduces star formation and produces less centrally
concentrated stellar profiles. These effects are most evident for the 1 keV
candidate but almost disappear for keV. All simulations
form similar stellar discs independent of WDM particle mass. In particular, the
disc scale length does not change when WDM is considered. The reduced amount of
star formation in the case of 1 keV particles is due to the effects of WDM on
merging satellites which are on average less concentrated and less gas rich.
The altered satellites cause a reduced starburst during mergers because they
trigger weaker disc instabilities in the main galaxy. Nevertheless we show that
disc galaxy evolution is much more sensitive to stellar feedback than it is to
WDM candidate mass. Overall we find that WDM, especially when restricted to
current observational constraints ( keV), has a minor
impact on disc galaxy formation.Comment: 13 pages, 9 figures, 2 tables; minor clarifications added in results
section, conclusions unchanged; accepted for publication in MNRA
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