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Service user involvement in the evaluation of psycho-social intervention for self-harm: a systematic literature review
Background: The efficacy of interventions and treatments for self-harm is well researched. Previous reviews of the literature have highlighted the lack of definitively effective interventions for self-harm and have highlighted the need for future research. These recommendations are also reflected in clinical guidelines published by the National Institute for Health and Clinical Excellence (NICE, 2004) which also call for service user involvement in studies of treatment efficacy. Aims: A systematic review was undertaken to determine i) what contributions service users have made to the evaluation of psychosocial interventions ii) by what methods have service users been involved iii) in what ways could service user involvement supplement empirical evidence for interventions
Slowly varying control parameters, delayed bifurcations and the stability of spikes in reaction-diffusion systems
We present three examples of delayed bifurcations for spike solutions of
reaction-diffusion systems. The delay effect results as the system passes
slowly from a stable to an unstable regime, and was previously analysed in the
context of ODE's in [P.Mandel, T.Erneux, J.Stat.Phys, 1987]. It was found that
the instability would not be fully realized until the system had entered well
into the unstable regime. The bifurcation is said to have been "delayed"
relative to the threshold value computed directly from a linear stability
analysis. In contrast, we analyze the delay effect in systems of PDE's. In
particular, for spike solutions of singularly perturbed generalized
Gierer-Meinhardt (GM) and Gray-Scott (GS) models, we analyze three examples of
delay resulting from slow passage into regimes of oscillatory and competition
instability. In the first example, for the GM model on the infinite real line,
we analyze the delay resulting from slowly tuning a control parameter through a
Hopf bifurcation. In the second example, we consider a Hopf bifurcation on a
finite one-dimensional domain. In this scenario, as opposed to the extrinsic
tuning of a system parameter through a bifurcation value, we analyze the delay
of a bifurcation triggered by slow intrinsic dynamics of the PDE system. In the
third example, we consider competition instabilities of the GS model triggered
by the extrinsic tuning of a feed rate parameter. In all cases, we find that
the system must pass well into the unstable regime before the onset of
instability is fully observed, indicating delay. We also find that delay has an
important effect on the eventual dynamics of the system in the unstable regime.
We give analytic predictions for the magnitude of the delays as obtained
through analysis of certain explicitly solvable nonlocal eigenvalue problems.
The theory is confirmed by numerical solutions of the full PDE systems.Comment: 31 pages, 20 figures, submitted to Physica D: Nonlinear Phenomen
Ecologic Relationships Between Bacteria and Algae in Mass Culture
Ecological relationships between bacteria and algae in mass cultur
Highly Ionised Gas as a Diagnostic of the Inner NLR
The spectra of AGN from the ultraviolet to the near infrared, exhibit
emission lines covering a wide range of ionisation states, from neutral species
such as [O I] 6300A, up to [Fe XIV] 5303A. Here we report on some recent
studies of the properties of highly ionised lines (HILs), plus two case studies
of individual objects. Future IFU observations at high spatial and good
spectral resolution, will probe the excitation and kinematics of the gas in the
zone between the extended NLR and unresolved BLR. Multi-component SED fitting
can be used to link the source of photoionisation with the strengths and ratios
of the HILs.Comment: Proceedings of the IAU Symposium: Co-evolution of Central Black Holes
and Galaxie
Remote sensing of changes in morphology and physiology of trees under stress Annual progress report
Remote sensing of morphological and physiological changes in trees under stres
Strong variability of the coronal line region in NGC 5548
We present the second extensive study of the coronal line variability in an
active galaxy. Our data set for the well-studied Seyfert galaxy NGC 5548
consists of five epochs of quasi-simultaneous optical and near-infrared
spectroscopy spanning a period of about five years and three epochs of X-ray
spectroscopy overlapping in time with it. Whereas the broad emission lines and
hot dust emission varied only moderately, the coronal lines varied strongly.
However, the observed high variability is mainly due to a flux decrease. Using
the optical [FeVII] and X-ray OVII emission lines we estimate that the coronal
line gas has a relatively low density of n~10^3/cm^3 and a relatively high
ionisation parameter of log U~1. The resultant distance of the coronal line gas
from the ionising source of about eight light years places this region well
beyond the hot inner face of the dusty torus. These results imply that the
coronal line region is an independent entity. We find again support for the
X-ray heated wind scenario of Pier & Voit; the increased ionising radiation
that heats the dusty torus also increases the cooling efficiency of the coronal
line gas, most likely due to a stronger adiabatic expansion. The much stronger
coronal line variability of NGC 5548 relative to that of NGC 4151 can also be
explained within this picture. NGC 5548 has much stronger coronal lines
relative to the low ionisation lines than NGC 4151 indicating a stronger wind,
in which case a stronger adiabatic expansion of the gas and so fading of the
line emission is expected.Comment: 10 pages, 6 figures; accepted for publication in MNRAS. arXiv admin
note: substantial text overlap with arXiv:1501.0292
Variability of the coronal line region in NGC 4151
We present the first extensive study of the coronal line variability in an
active galaxy. Our data set for the nearby source NGC 4151 consists of six
epochs of quasi-simultaneous optical and near-infrared spectroscopy spanning a
period of about eight years and five epochs of X-ray spectroscopy overlapping
in time with it. None of the coronal lines showed the variability behaviour
observed for the broad emission lines and hot dust emission. In general, the
coronal lines varied only weakly, if at all. Using the optical [Fe VII] and
X-ray O VII emission lines we estimate that the coronal line gas has a
relatively low density of n~10^3 cm^-3 and a relatively high ionisation
parameter of log U~1. The resultant distance of the coronal line gas from the
ionising source is about two light years, which puts this region well beyond
the hot inner face of the obscuring dusty torus. The high ionisation parameter
implies that the coronal line region is an independent entity rather than part
of a continuous gas distribution connecting the broad and narrow emission line
regions. We present tentative evidence for the X-ray heated wind scenario of
Pier & Voit. We find that the increased ionising radiation that heats the dusty
torus also increases the cooling efficiency of the coronal line gas, most
likely due to a stronger adiabatic expansion.Comment: 12 pages, 9 figures; accepted by MNRA
Origin and roles of a strong electron-phonon interaction in cuprate oxide superconductors
A strong electron-phonon interaction arises from the modulation of the
superexchange interaction by phonons. As is studied in Phys. Rev. B 70, 184514
(2004), Cu-O bond stretching modes can be soft around (pm pi/a, 0) and (0, pm
pi/a), with a the lattice constant of CuO_2 planes. In the critical region of
SDW, where antiferromagnetic spin fluctuations are developed around nesting
wave numbers Q of the Fermi surface, the stretching modes can also be soft
around 2Q. Almost symmetric energy dependences of the 2Q component of the
density of states, which are observed in the so called stripe and checker-board
states, cannot be explained by CDW with 2Q following the complete softening of
the 2Q modes, but they can be explained by a second-harmonic effect of SDW with
Q. The strong electron-phonon interaction can play no or only a minor role in
the occurrence of superconductivity.Comment: 5 pages, 1 fugur
Fast Hands-free Writing by Gaze Direction
We describe a method for text entry based on inverse arithmetic coding that
relies on gaze direction and which is faster and more accurate than using an
on-screen keyboard.
These benefits are derived from two innovations: the writing task is matched
to the capabilities of the eye, and a language model is used to make
predictable words and phrases easier to write.Comment: 3 pages. Final versio
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