5,257 research outputs found
WMAP 3yr data with the CCA: anomalous emission and impact of component separation on the CMB power spectrum
The Correlated Component Analysis (CCA) allows us to estimate how the
different diffuse emissions mix in CMB experiments, exploiting also
complementary information from other surveys. It is especially useful to deal
with possible additional components. An application of CCA to WMAP maps
assuming that only the canonical Galactic emissions are present, highlights the
widespread presence of a spectrally flat "synchrotron" component, largely
uncorrelated with the synchrotron template, suggesting that an additional
foreground is indeed required. We have tested various spectral shapes for such
component, namely a power law as expected if it is flat synchrotron, and two
spectral shapes that may fit the spinning dust emission: a parabola in the logS
- log(frequency) plane, and a grey body. Quality tests applied to the
reconstructed CMB maps clearly disfavour two of the models. The CMB power
spectra, estimated from CMB maps reconstructed exploiting the three surviving
foreground models, are generally consistent with the WMAP ones, although at
least one of them gives a significantly higher quadrupole moment than found by
the WMAP team. Taking foreground modeling uncertainties into account, we find
that the mean quadrupole amplitude for the three "good" models is less than 1
sigma below the expectation from the standard LambdaCDM model. Also the other
reported deviations from model predictions are found not to be statistically
significant, except for the excess power at l~40. We confirm the evidence for a
marked North-South asymmetry in the large scale (l < 20) CMB anisotropies. We
also present a first, albeit preliminary, all-sky map of the "anomalous"
component.Comment: 14 pages, 17 figures, submitted to MNRAS, references adde
Gender violence in schools: taking the ‘girls-as-victims’ discourse forward
This paper draws attention to the gendered nature of violence in schools. Recent recognition that schools can be violent places has tended to ignore the fact that many such acts originate in unequal and antagonistic gender relations, which are tolerated and ‘normalised’ by everyday school structures and processes. After examining some key concepts and definitions, we provide a brief overview of the scope and various manifestations of gender violence in schools, noting that most research to date has focused on girls as victims of gender violence within a heterosexual context and ignores other forms such as homophobic and girl violence. We then move on to look at a few interventions designed to address gender violence in schools in the developing world and end by highlighting the need for more research and improved understanding of the problem and how it can be addressed
Age differences in mental health literacy
BACKGROUND: The community's knowledge and beliefs about mental health problems, their risk
factors, treatments and sources of help may vary as a function of age.
METHODS: Data were taken from an epidemiological survey conducted during 2003–2004 with a
national clustered sample of Australian adults aged 18 years and over. Following the presentation
of a vignette describing depression (n = 1001) or schizophrenia (n = 997), respondents were asked
a series of questions relating to their knowledge and recognition of the disorder, beliefs about the
helpfulness of treating professionals and medical, psychological and lifestyle treatments, and likely
causes.
RESULTS: Participant age was coded into five categories and cross-tabulated with mental health
literacy variables. Comparisons between age groups revealed that although older adults (70+ years)
were poorer than younger age groups at correctly recognising depression and schizophrenia, young
adults (18–24 years) were more likely to misidentify schizophrenia as depression. Differences were
also observed between younger and older age groups in terms of beliefs about the helpfulness of
certain treating professionals and medical and lifestyle treatments for depression and
schizophrenia, and older respondents were more likely to believe that schizophrenia could be
caused by character weakness.
CONCLUSION: Differences in mental health literacy across the adult lifespan suggest that more
specific, age appropriate messages about mental health are required for younger and older age
groups. The tendency for young adults to 'over-identify' depression signals the need for awareness
campaigns to focus on differentiation between mental disorders
Wear and Friction Modeling on Lifeboat Launch Systems
The RNLI provides search and rescue cover along the UK and RoI coast using a variety of lifeboats
and launch techniques. In locations where there is no natural harbour it is necessary to use a slipway
to launch the lifeboat into the sea. Lifeboat slipway stations consist of an initial section where the
boat is held on rollers followed by an inclined keelway lined with low friction composite materials,
the lifeboat is released from the top of the slipway and proceeds under its own weight into the water.
The lifeboat is later recovered using a winch line. It is common to manually apply grease to the
composite slipway lining before each launch and recovery in order to ensure sufficiently low friction
for successful operation. With the introduction of the Tamar class lifeboat it is necessary to upgrade
existing boathouses and standardise slipway operational procedures to ensure consistent operation.
The higher contact pressures associated with the new lifeboat have led to issues of high friction and
wear on the composite slipway linings and the manual application of grease to reduce friction is to be
restricted due to environmental impact and cost factors. This paper presents a multidisciplinary
approach to modelling slipway panel wear and friction using tribometer testing in conjunction with
finite element analysis and slipway condition surveys to incorporate common real-world effects such
as panel misalignments. Finally, it is shown that a freshwater lubrication system is effective,
reducing cost and environmental impacts while maintaining good friction and wear performance
Analytic Behaviour of Competition among Three Species
We analyse the classical model of competition between three species studied
by May and Leonard ({\it SIAM J Appl Math} \textbf{29} (1975) 243-256) with the
approaches of singularity analysis and symmetry analysis to identify values of
the parameters for which the system is integrable. We observe some striking
relations between critical values arising from the approach of dynamical
systems and the singularity and symmetry analyses.Comment: 14 pages, to appear in Journal of Nonlinear Mathematical Physic
A dynamical system approach to higher order gravity
The dynamical system approach has recently acquired great importance in the
investigation on higher order theories of gravity. In this talk I review the
main results and I give brief comments on the perspectives for further
developments.Comment: 6 pages, 1 figure, 2 tables, talk given at IRGAC 2006, July 200
Investigating Biological Matter with Theoretical Nuclear Physics Methods
The internal dynamics of strongly interacting systems and that of
biomolecules such as proteins display several important analogies, despite the
huge difference in their characteristic energy and length scales. For example,
in all such systems, collective excitations, cooperative transitions and phase
transitions emerge as the result of the interplay of strong correlations with
quantum or thermal fluctuations. In view of such an observation, some
theoretical methods initially developed in the context of theoretical nuclear
physics have been adapted to investigate the dynamics of biomolecules. In this
talk, we review some of our recent studies performed along this direction. In
particular, we discuss how the path integral formulation of the molecular
dynamics allows to overcome some of the long-standing problems and limitations
which emerge when simulating the protein folding dynamics at the atomistic
level of detail.Comment: Prepared for the proceedings of the "XII Meeting on the Problems of
Theoretical Nuclear Physics" (Cortona11
Symmetry, singularities and integrability in complex dynamics III: approximate symmetries and invariants
The different natures of approximate symmetries and their corresponding first
integrals/invariants are delineated in the contexts of both Lie symmetries of
ordinary differential equations and Noether symmetries of the Action Integral.
Particular note is taken of the effect of taking higher orders of the
perturbation parameter. Approximate symmetries of approximate first
integrals/invariants and the problems of calculating them using the Lie method
are considered
Local political leadership and the modernisation of local government
Political leadership has been a key element of central government’s attempts to ‘modernise’ local government over the past decade, within a discourse that emphasised ‘strong’ and ‘visible’ leadership and the role of leaders and leadership in driving change within local authorities. In the context of such an approach, and also taking account of academic discourse, this article draws upon interviews with nearly thirty individuals in leadership positions in local authorities in England, Scotland and Wales to assess their experiences of leadership and their views of some aspects of the role and work of councils. It suggests that whilst there is broad convergence between the aspirations of government and the narratives that emerge from these leaders on some aspects of local political leadership, there are also differences, perhaps most notably over the relationship between changes to decision making structures and the loci of political power
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