10,554 research outputs found
Data analysis of continuous gravitational wave: Fourier transform-I
We present the Fourier Transform of a continuous gravitational wave. We have
analysed the data set for one day observation time and our analysis is
applicable for arbitrary location of detector and source. We have taken into
account the effects arising due to rotational as well as orbital motions of the
earth.Comment: Accepted in MNRAS, 22 pages, 9 figure
Caring for continence in stroke care settings: a qualitative study of patientsâ and staff perspectives on the implementation of a new continence care intervention
Objectives: Investigate the perspectives of patients and nursing staff on the implementation of an augmented continence care intervention after stroke.
Design: Qualitative data were elicited during semi-structured interviews with patients (nâ=â15) and staff (14 nurses; nine nursing assistants) and analysed using thematic analysis.
Setting: Mixed acute and rehabilitation stroke ward.
Participants: Stroke patients and nursing staff that experienced an enhanced continence care intervention.
Results: Four themes emerged from patientsâ interviews describing: (a) challenges communicating about continence (initiating conversations and information exchange); (b) mixed perceptions of continence care; (c) ambiguity of focus between mobility and continence issues; and (d) inconsistent involvement in continence care decision making. Patientsâ perceptions reflected the severity of their urinary incontinence. Staff described changes in: (i) knowledge as a consequence of specialist training; (ii) continence interventions (including the development of nurse-led initiatives to reduce the incidence of unnecessary catheterisation among patients admitted to their ward); (iii) changes in attitude towards continence from containment approaches to continence rehabilitation; and (iv) the challenges of providing continence care within a stroke care context including limitations in access to continence care equipment or products, and institutional attitudes towards continence.
Conclusion: Patients (particularly those with severe urinary incontinence) described challenges communicating about and involvement in continence care decisions. In contrast, nurses described improved continence knowledge, attitudes and confidence alongside a shift from containment to rehabilitative approaches. Contextual components including care from point of hospital admission, equipment accessibility and interdisciplinary approaches were perceived as important factors to enhancing continence care
Target enrichment of ultraconserved elements from arthropods provides a genomic perspective on relationships among Hymenoptera
Gaining a genomic perspective on phylogeny requires the collection of data
from many putatively independent loci collected across the genome. Among
insects, an increasingly common approach to collecting this class of data
involves transcriptome sequencing, because few insects have high-quality genome
sequences available; assembling new genomes remains a limiting factor; the
transcribed portion of the genome is a reasonable, reduced subset of the genome
to target; and the data collected from transcribed portions of the genome are
similar in composition to the types of data with which biologists have
traditionally worked (e.g., exons). However, molecular techniques requiring RNA
as a template are limited to using very high quality source materials, which
are often unavailable from a large proportion of biologically important insect
samples. Recent research suggests that DNA-based target enrichment of conserved
genomic elements offers another path to collecting phylogenomic data across
insect taxa, provided that conserved elements are present in and can be
collected from insect genomes. Here, we identify a large set (n1510) of
ultraconserved elements (UCE) shared among the insect order Hymenoptera. We use
in silico analyses to show that these loci accurately reconstruct relationships
among genome-enabled Hymenoptera, and we design a set of baits for enriching
these loci that researchers can use with DNA templates extracted from a variety
of sources. We use our UCE bait set to enrich an average of 721 UCE loci from
30 hymenopteran taxa, and we use these UCE loci to reconstruct phylogenetic
relationships spanning very old (220 MYA) to very young (1 MYA)
divergences among hymenopteran lineages. In contrast to a recent study
addressing hymenopteran phylogeny using transcriptome data, we found ants to be
sister to all remaining aculeate lineages with complete support
Leakage of waves from coronal loops by wave tunneling
To better understand the decay of vertically polarised fast kink modes of coronal loops by the mechanism of wave tunneling, simulations are performed of fast kink modes in straight flux slabs which have AlfvĂ©n speed profiles which include a tunneling region. The decay rates are found to be determined by the mode number of the trapped mode and the thickness of the tunneling region. Two analytical models are suggested to explain the observed decay. The first is a extension of the work of Roberts (1981, Sol. Phys., 69, 39) to include a finite thickness tunneling region, and the second is a simpler model which yields an analytical solution for the relationship between decay rate, period and the thickness of the tunneling region. The decay rates for these straight slabs are found to be slower than in observations and those found in a previous paper on the subject by Brady & Arber (2005, A&A, 438, 733) using curved flux slabs. It is found that the diïŹerence between the straight slabs used here and the curved slabs used in Brady & Arber (2005, A&A, 438, 733) can be represented as a geometric correction to the decay rate
Stability of degenerate Cauchy horizons in black hole spacetimes
In the multihorizon black hole spacetimes, it is possible that there are
degenerate Cauchy horizons with vanishing surface gravities. We investigate the
stability of the degenerate Cauchy horizon in black hole spacetimes. Despite
the asymptotic behavior of spacetimes (flat, anti-de Sitter, or de Sitter), we
find that the Cauchy horizon is stable against the classical perturbations, but
unstable quantum mechanically.Comment: Revtex, 4 pages, no figures, references adde
Unreported summary statistics in trial publications and risk of bias in stroke rehabilitation systematic reviews: an international survey of review authors and examination of practical solutions
Breast Cancer: Modelling and Detection
This paper reviews a number of the mathematical models used in cancer modelling and then chooses a specific cancer, breast carcinoma, to illustrate how the modelling can be used in aiding detection. We then discuss mathematical models that underpin mammographic image analysis, which complements models of tumour growth and facilitates diagnosis and treatment of cancer. Mammographic images are notoriously difficult to interpret, and we give an overview of the primary image enhancement technologies that have been introduced, before focusing on a more detailed description of some of our own recent work on the use of physics-based modelling in mammography. This theoretical approach to image analysis yields a wealth of information that could be incorporated into the mathematical models, and we conclude by describing how current mathematical models might be enhanced by use of this information, and how these models in turn will help to meet some of the major challenges in cancer detection
Data analysis of continuous gravitational wave: All sky search and study of templates
We have studied the problem of all sky search in reference to continuous
gravitational wave particularly for such sources whose wave-form are known in
advance. We have made an analysis of the number of templates required for
matched filter analysis as applicable to these sources. We have employed the
concept of {\it fitting factor} {\it (FF)}; treating the source location as the
parameters of the signal manifold and have studied the matching of the signal
with templates corresponding to different source locations. We have
investigated the variation of FF with source location and have noticed a
symmetry in template parameters, and . It has been found
that the two different template values in source location, each in
and , have same {\it FF}. We have also computed the number of templates
required assuming the noise power spectral density to be flat. It is
observed that higher {\it FF} requires exponentially increasing large number of
templates.Comment: Accepted in MNRAS, 14 pages, 5 figure
Jensen-Shannon divergence as a measure of distinguishability between mixed quantum states
We discuss an alternative to relative entropy as a measure of distance
between mixed quantum states. The proposed quantity is an extension to the
realm of quantum theory of the Jensen-Shannon divergence (JSD) between
probability distributions. The JSD has several interesting properties. It
arises in information theory and, unlike the Kullback-Leibler divergence, it is
symmetric, always well defined and bounded. We show that the quantum JSD (QJSD)
shares with the relative entropy most of the physically relevant properties, in
particular those required for a "good" quantum distinguishability measure. We
relate it to other known quantum distances and we suggest possible applications
in the field of the quantum information theory.Comment: 14 pages, corrected equation 1
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