438 research outputs found
SO(5) Invariance and Effective Field Theory for High-Tc Superconductors
We set up the effective field theories which describe the SO(5)-invariant
picture of the high-Tc cuprates in various regimes. We use these to get
quantitative conclusions concerning the size of SO(5)-breaking effects. We
consider two applications in detail: (i) the thermodynamic free energy, which
describe the phase diagram and critical behaviour, and (ii) the Lagrangian
governing the interactions of the pseudo-Goldstone bosons with each other and
with the electron quasiparticles deep within the ordered phases. We use these
effective theories to obtain predictions for the critical behaviour near the
possible bicritical point and the pseudo-Goldstone boson dispersion relations,
as well as some preliminary results concerning their contribution to response
functions. We systematically identify which predictions are independent of the
microscopic details of the underlying electron dynamics, and which depend on
more model-dependent assumptions.Comment: 40 pages, plain TeX, companion article for the letter
cond-mat/961107
LoCuSS: First Results from Strong-lensing Analysis of 20 Massive Galaxy Clusters at z~0.2
We present a statistical analysis of a sample of 20 strong lensing clusters
drawn from the Local Cluster Substructure Survey (LoCuSS), based on high
resolution Hubble Space Telescope imaging of the cluster cores and follow-up
spectroscopic observations using the Keck-I telescope. We use detailed
parameterized models of the mass distribution in the cluster cores, to measure
the total cluster mass and fraction of that mass associated with substructures
within R<250kpc.These measurements are compared with the distribution of
baryons in the cores, as traced by the old stellar populations and the X-ray
emitting intracluster medium. Our main results include: (i) the distribution of
Einstein radii is log-normal, with a peak and 1sigma width of
=1.16+/-0.28; (ii) we detect an X-ray/lensing mass discrepancy of
=1.3 at 3 sigma significance -- clusters with larger substructure
fractions displaying greater mass discrepancies, and thus greater departures
from hydrostatic equilibrium; (iii) cluster substructure fraction is also
correlated with the slope of the gas density profile on small scales, implying
a connection between cluster-cluster mergers and gas cooling. Overall our
results are consistent with the view that cluster-cluster mergers play a
prominent role in shaping the properties of cluster cores, in particular
causing departures from hydrostatic equilibrium, and possibly disturbing cool
cores. Our results do not support recent claims that large Einstein radius
clusters present a challenge to the CDM paradigm.Comment: 28 pages, 14 figures, accepted for publication in MNRAS, replaced
with accepted versio
Exploring the experiences of young people nursed on adult wards
This paper reports on a study of experiences of young people aged 14 to 18 years who were nursed on acute adult hospital wards in NHS hospitals in England. In spite of British government guidelines, young people from 14 years of age continue to be admitted to adult wards in the UK. Although much has been written about the transition of the young person to adult services there is little research about the experiences of young people who are nursed on adult wards.Hermeneutic phenomenology was used to explore the lived experiences of eight young people who had been nursed on adult wards between 2004 and 2010. Data were collected in 2010. In-depth interviews were recorded, transcribed and analysed using Colaizzi’s framework (Colaizzi, 1978). Themes explored included expectations of what the experience may be like, young people’s first impressions of the ward environment, the feelings of the young person while in hospital, the attitudes of people towards them including—both staff and other patients, and finally, future admissions and how they would cope with readmissions. Better provision needs to be made for young people including appropriately trained staff, adolescent friendly environments and areas in adult wards that are dedicated to adolescents
Mystify me: Coke, terror and the symbolic immortality boost
A panel on “Marketing as Mystification” convened at the 2011 Academy of Marketing conference in Liverpool. Ideas from the Liverpool event were supplemented by commentaries from selected other authors. Each commentary explores the aspects of “mystification” observable in marketing discourses and practices. In what follows, Laufer interprets marketing mystification as modern form of sophism, Dholakia and Firat discuss mystifying ways that inequality is marketed, Varman analyzes the perversion and mystification of “development” via neoliberal marketing of “social entrepreneurship,” Mikkonen explores mystifying marketing representations of gays and lesbians, and Freund and Jacobi present a fascinating interpretation of how Coca-Cola advertising mystically reassures us that our difficult, dangerous lifeworld is actually quite hunky-dory. </jats:p
(Un)twisted: talking back to media representations of eating disorders
In 2014-15, there were several news reports about a rise in the diagnoses and treatment of eating disorders (EDs), as attributed to the use of image-driven social media. Such coverage can be situated within a long history of concern in which those diagnosed with an ED are constructed as ‘especially vulnerable’ to the power of media images – a subjectivity which is pathologised and devalued precisely through its association with femininity. The most incisive objections to EDs being presented as a response to the ‘weight’ of media representation have come from Abigail Bray (2005) in her work on how anorexia is constructed as a reading as well as an eating disorder. Indeed, there is a whole history of empirical work in Feminist Media Studies and Girlhood Studies which has challenged the pernicious construction of female subjectivity as ‘excessively’ invested in, and ‘damaged’ by, the consumption of mass mediated forms. Yet the media consumption practices of those with experience of an ED have not been subject to similar feminist re-evaluation – an omission which this research seeks to address. In exploring the results of 17 semi-structured interviews with people who have experience of an ED discussing their encounters with media representations of EDs (material that is often co-opted into debates about the ‘toxic’ nature of media culture in this regard), this article seeks to intervene in how such imagined media consumption practices are often defined. In seeking to speak back to historically pathologising constructions, the article seeks to explore the qualitative responses in the context of more ‘every day’ understandings of media engagement, thus working against the gendered othering which has persistently occurred
Fine-Tuning Translation Kinetics Selection as the Driving Force of Codon Usage Bias in the Hepatitis A Virus Capsid
Hepatitis A virus (HAV), the prototype of genus Hepatovirus, has several unique biological characteristics that distinguish it from other members of the Picornaviridae family. Among these, the need for an intact eIF4G factor for the initiation of translation results in an inability to shut down host protein synthesis by a mechanism similar to that of other picornaviruses. Consequently, HAV must inefficiently compete for the cellular translational machinery and this may explain its poor growth in cell culture. In this context of virus/cell competition, HAV has strategically adopted a naturally highly deoptimized codon usage with respect to that of its cellular host. With the aim to optimize its codon usage the virus was adapted to propagate in cells with impaired protein synthesis, in order to make tRNA pools more available for the virus. A significant loss of fitness was the immediate response to the adaptation process that was, however, later on recovered and more associated to a re-deoptimization rather than to an optimization of the codon usage specifically in the capsid coding region. These results exclude translation selection and instead suggest fine-tuning translation kinetics selection as the underlying mechanism of the codon usage bias in this specific genome region. Additionally, the results provide clear evidence of the Red Queen dynamics of evolution since the virus has very much evolved to re-adapt its codon usage to the environmental cellular changing conditions in order to recover the original fitness
Viewpoint survey of mental health service users’ experiences of discrimination in England 2008–2012
Physics searches at the LHC
With the LHC up and running, the focus of experimental and theoretical high
energy physics will soon turn to an interpretation of LHC data in terms of the
physics of electroweak symmetry breaking and the TeV scale. We present here a
broad review of models for new TeV-scale physics and their LHC signatures. In
addition, we discuss possible new physics signatures and describe how they can
be linked to specific models of physics beyond the Standard Model. Finally, we
illustrate how the LHC era could culminate in a detailed understanding of the
underlying principles of TeV-scale physics.Comment: 184 pages, 55 figures, 14 tables, hundreds of references; scientific
feedback is welcome and encouraged. v2: text, references and Overview Table
added; feedback still welcom
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