3,823 research outputs found
Design specification for LARSYS procedure 1
There are no author-identified significant results in this report
Solar Coronal Structures and Stray Light in TRACE
Using the 2004 Venus transit of the Sun to constrain a semi-empirical
point-spread function for the TRACE EUV solar telescope, we have measured the
effect of stray light in that telescope. We find that 43% of 171A EUV light
that enters TRACE is scattered, either through diffraction off the entrance
filter grid or through other nonspecular effects. We carry this result forward,
via known-PSF deconvolution of TRACE images, to identify its effect on analysis
of TRACE data. Known-PSF deconvolution by this derived PSF greatly reduces the
effect of visible haze in the TRACE 171A images, enhances bright features, and
reveals that the smooth background component of the corona is considerably less
bright (and hence much more rarefied) than commonly supposed. Deconvolution
reveals that some prior conlclusions about the Sun appear to have been based on
stray light in the images. In particular, the diffuse background "quiet corona"
becomes consistent with hydrostatic support of the coronal plasma; feature
contrast is greatly increased, possibly affecting derived parameters such as
the form of the coronal heating function; and essentially all existing
differential emission measure studies of small features appear to be affected
by contamination from nearby features. We speculate on further implications of
stray light for interpretation of EUV images from TRACE and similar
instruments, and advocate deconvolution as a standard tool for image analysis
with future instruments such as SDO/AIA.Comment: Accepted by APJ; v2 reformatted to single-column format for online
readabilit
The Optical Polarization and Warm Absorber in IRAS 17020+4544
We report the detection of ionized absorption in the ASCA spectrum of the
narrow-line Seyfert 1 galaxy IRAS 17020+4544. Subsequent optical
spectropolarimetry revealed high polarization increasing from 3% in the red to
5% in the blue, indicating electron or dust scattering as a likely origin. The
broad emission line H is somewhat less polarized than the continuum,
supporting a location of the polarizing material within the AGN. The Balmer
line decrement and reddened optical spectrum support the presence of a dusty
warm absorber in this object.
We compared the broad band optical polarization and ionized X-ray absorption
of a collection of Seyfert 1 and 1.5 galaxies, excluding classes of objects
that are likely to have significant neutral X-ray absorption. Warm absorber
objects are generally more likely to have high optical polarization than
objects with no detected ionized absorption. This result lends additional
support to the idea that the warm absorber is associated with dust and implies
either that dust transmission is responsible for at least part of the
polarization or that the polarization is revealed because of the dimming of the
optical spectrum. Spectropolarimetry of Seyfert 1s generally locates the
scattering material inside the narrow-line region and often close to or within
the broad line region, consistent with estimates of the location of the dusty
warm absorber.Comment: 11 pages using (AASTeX) aaspp4.sty and 3 Postscript figures. Accepted
for publication in Astrophysical Journal Letter
Symmetry breaking due to Dzyaloshinsky-Moriya interactions in the kagome lattice
Due to the particular geometry of the kagom\'e lattice, it is shown that
antisymmetric Dzyaloshinsky-Moriya interactions are allowed and induce magnetic
ordering. The symmetry of the obtained low temperature magnetic phases are
studied through mean field approximation and classical Mont\'e Carlo
simulations. A phase diagram relating the geometry of the interaction and the
ordering temperature has been derived. The order of magnitude of the
anisotropies due to Dzyaloshinsky-Moriya interactions are more important than
in non-frustrated magnets, which enhances its appearance in real systems.
Application to the jarosites compounds is proposed. In particular, the low
temperature behaviors of the Fe and Cr-based jarosites are correctly described
by this model.Comment: 6 (revtex4) twocolumn pages, 6 .eps figures. Submitted to Phys. Rev.
Vesignieite: a kagome antiferromagnet with dominant third-neighbor exchange
The spin- kagome antiferromagnet is an archetypal frustrated
system predicted to host a variety of exotic magnetic states. We show using
neutron scattering measurements that deuterated vesignieite
BaCuVO(OD), a fully stoichiometric kagome
magnet with 1% lattice distortion, orders magnetically at
K into a multi-k coplanar variant of the predicted triple-k
octahedral structure. We find this structure is stabilized by a dominant
antiferromagnetic 3-neighbor exchange with minor
1- or 2--neighbour exchange. The spin-wave
spectrum is well described by a -only model including a tiny symmetric
exchange anisotropy
Involving Lived Experience in regional efforts to address gambling-related harms: going beyond ‘window dressing’ and ‘tick box exercises’
Background
Lived Experience (LE) involvement has been shown to improve interventions across diverse sectors. Yet LE contributions to public health approaches to address gambling-related harms remain underexplored, despite notable detrimental health and social outcomes linked to gambling. This paper analyses the potential of LE involvement in public health strategy to address gambling-related harms. It focuses on the example of a UK city-region gambling harms reduction intervention that presented multiple opportunities for LE input.
Methods
Three focus groups and 33 semi-structured interviews were conducted to hear from people with and without LE who were involved in the gambling harms reduction intervention, or who had previous experience of LE-informed efforts for addressing gambling-related harms. People without LE provided reflections on the value and contributions of others’ LE to their work. Data analysis combined the Framework Method with themes developed inductively (from people’s accounts) and deductively (from the literature, including grey literature).
Results
Four themes were identified: (1) personal journeys to LE involvement; (2) the value added by LE to interventions for addressing gambling-related harms; (3) emotional impacts on people with LE; and (4) collective LE and diverse lived experiences. Two figures outlining LE involvement specific to gambling harms reduction in the UK, where public health efforts aimed at addressing gambling-related harms coexist with industry-funded programmes, are proposed.
Conclusions
Integrating a range of LE perspectives in a public health approach to gambling harms reduction requires local access to involvement for people with LE via diverse routes that are free from stigma and present people with LE with options in how they can engage and be heard in decision-making, and how they operate in relation to industry influence. Involving LE in gambling harms reduction requires enabling people to develop the affective and critical skills necessary to navigate complex emotional journeys and a challenging commercial and policy environment
Best of Breed IT Strategy: An Alternative to Enterprise Resource Planning Systems
Enterprise Resource Planning (ERP) software has become the dominant strategic platform for supporting enterprise-wide business processes. However, single vendor ERP software systems have been criticised for not meeting specific organisation and industry requirements. An alternative approach ‘Best of Breed (BoB)’, integrates components of software from multiple standard package vendors, and in some cases custom components. The objective is to develop enterprise systems that are more closely aligned with the requirements of an organisation. Although this approach may not be common at present it is likely to grow in importance due to business needs and technology advances such as the componentisation of ERP software. A case study analysis of a BoB implementation at a global entertainment\u27s company is used as a platform for the discussion of the issues associated with this strategy and a comparison is made with the single vendor ERP alternative. The analysis centres on the complexity of implementation, the differences in the levels of functionality and business fit and the maintenance requirements
Quantum Kagome antiferromagnet ZnCu3(OH)6Cl2
The frustration of antiferromagnetic interactions on the loosely connected
kagome lattice associated to the enhancement of quantum fluctuations for S=1/2
spins was acknowledged long ago as a keypoint to stabilize novel ground states
of magnetic matter. Only very recently, the model compound Herbersmithite,
ZnCu3(OH)6Cl2, a structurally perfect kagome antiferromagnet, could be
synthesized and enables a close comparison to theories. We review and classify
various experimental results obtained over the past years and underline some of
the pending issues.Comment: 23 pages, 16 figures, invited paper in J. Phys. Soc. Jpn, special
topics issue on "Novel States of Matter Induced by Frustration", to be
published in Jan. 201
Harnessing lived experience in a community-based intervention to address gambling-related harms
Background Lived experience of people directly or indirectly affected by public health issues can provide unique insights into how to improve interventions. Increasing availability of gambling necessitates involving communities in efforts to reduce gambling-related harms. This presentation reports qualitative exploratory research into the value of lived experience across a city-region gambling harm reduction initiative in the UK. Methods Focus groups and interviews were used to explore the practical application of lived experience with participants: advisory panel members, external stakeholders, community project staff, and public health professionals. Collaborative data analysis combined the framework method with theme development inductively (from participants’ accounts) and deductively (from academic and grey literature). Results Four themes were identified: (1) lived experience spans formal and informal settings with different activities and personal impacts; (2) organic and structured pathways to lived experience involvement coexist; (3) the emotional work of people affected by gambling-related harms ranges from frustration at policy inertia to deeper understanding of their own recovery journey; and (4) lived experience encompasses diverse experiential knowledges. Conclusions Involving lived experience in this intervention increased participants’ awareness of the harmful role of the gambling industry and critical reflection on the representativeness of lived experience. Harnessing lived experience at a regional level requires multi-setting support free from stigma and industry influence to ensure the sustained vitality of a diverse lived experience community specialised in gambling-related harms and equipped to navigate conflicting emotions and a challenging policy environment. Key messages • Increasing availability of gambling necessitates involving communities in efforts to reduce gambling-related harms. • The use of lived experience in gambling-related harms prevention efforts and research can inform intervention development
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