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What do I do now? Intolerance of uncertainty is associated with discrete patterns of anticipatory physiological responding to different contexts
Heightened physiological responses to uncertainty are a common hallmark of anxiety disorders. Many separate studies have examined the relationship between individual differences in intolerance of uncertainty (IU) and physiological responses to uncertainty during different contexts. Despite this there is a scarcity of research examining the extent to which individual differences in IU are related to shared or discrete patterns of anticipatory physiological responding across different contexts. Anticipatory physiological responses to uncertainty were assessed in three different contexts (associative threat learning and extinction, threat uncertainty, decision-making) within the same sample (n = 45). During these tasks, behavioural responses (i.e. reaction times, choices), skin conductance and corrugator supercilli activity were recorded. In addition, self-reported IU and trait anxiety were measured. IU was related to both skin conductance and corrugator supercilii activity for the associative threat learning and extinction context, and decision-making context. However, trait anxiety was related to corrugator supercilii activity during the threat uncertainty context. Ultimately, this research helps us further tease apart the role of IU on different aspects of anticipation (i.e. valence and arousal) across contexts, which will be relevant for future IU-related models of psychopathology
Lyapunov instability for a periodic Lorentz gas thermostated by deterministic scattering
In recent work a deterministic and time-reversible boundary thermostat called
thermostating by deterministic scattering has been introduced for the periodic
Lorentz gas [Phys. Rev. Lett. {\bf 84}, 4268 (2000)]. Here we assess the
nonlinear properties of this new dynamical system by numerically calculating
its Lyapunov exponents. Based on a revised method for computing Lyapunov
exponents, which employs periodic orthonormalization with a constraint, we
present results for the Lyapunov exponents and related quantities in
equilibrium and nonequilibrium. Finally, we check whether we obtain the same
relations between quantities characterizing the microscopic chaotic dynamics
and quantities characterizing macroscopic transport as obtained for
conventional deterministic and time-reversible bulk thermostats.Comment: 18 pages (revtex), 7 figures (postscript
Developing a framework for the analysis of power through depotentia
Stakeholder participation in tourism policy-making is usually perceived as providing a means of empowerment. However participatory processes drawing upon stakeholders from traditionally empowered backgrounds may provide the means of removing empowerment from stakeholders. Such an outcome would be in contradiction to the claims that participatory processes improve both inclusivity and sustainability. In order to form an understanding of the sources through which empowerment may be removed, an analytical perspective has been developed deriving from LukesĂŻÂżÂœs views of power dating from 1974. This perspective considers the concept of depotentia as the removal of ĂŻÂżÂœpower toĂŻÂżÂœ without speculating upon the underlying intent and also provides for the multidimensionality of power to be examined within a single study. The application of this analytical perspective has been tested upon findings of the government-commissioned report of the Countryside and Community Research Unit in 2005. The survey and report investigated the progress of Local Access Forums in England created in response to the Countryside and Rights of Way Act 2000. Consideration of the data from this perspective permits the classification of individual sources of depotentia which can each be addressed and potentially enable stakeholder groups to reverse loss of empowerment where it has occurred
Fatigue Intervention by Nurses Evaluation - The FINE Trial. A randomised controlled trial of nurse led self-help treatment for patients in primary care with chronic fatigue syndrome: study protocol. [ISRCTN74156610]
Background: Chronic fatigue syndrome, also known as ME (CFS/ME), is a condition characterised primarily by severe, disabling fatigue, of unknown origin, which has a poor prognosis and serious personal and economic consequences. Evidence for the effectiveness of any treatment for CFS/ME in primary care, where most patients are seen, is sparse. Recently, a brief, pragmatic treatment for CFS/ME, based on a physiological dysregulation model of the condition, was shown to be successful in improving fatigue and physical functioning in patients in secondary care. The treatment involves providing patients with a readily understandable explanation of their symptoms, from which flows the rationale for a graded rehabilitative plan, developed collaboratively with the therapist. The present trial will test the effectiveness and cost-effectiveness of pragmatic rehabilitation when delivered by specially trained general nurses in primary care. We selected a client-centred counselling intervention, called supportive listening, as a comparison treatment. Counselling has been shown to be as effective as cognitive behaviour therapy for treating fatigue in primary care, is more readily available, and controls for supportive therapist contact time. Our control condition is treatment as usual by the general practitioner (GP). Methods and design: This study protocol describes the design of an ongoing, single-blind, pragmatic randomized controlled trial of a brief (18 week) self-help treatment, pragmatic rehabilitation, delivered by specially trained nurse-therapists in patients' homes, compared with nurse-therapist delivered supportive listening and treatment as usual by the GP. An economic evaluation, taking a societal viewpoint, is being carried out alongside the clinical trial. Three adult general nurses were trained over a six month period to deliver the two interventions. Patients aged over 18 and fulfilling the Oxford criteria for CFS are assessed at baseline, after the intervention, and again one year later. Primary outcomes are self-reported physical functioning and fatigue at one year, and will be analysed on an intention-to-treat basis. A qualitative study will examine the interventions' mechanisms of change, and also GPs' drivers and barriers towards referral
Steady shear flow thermodynamics based on a canonical distribution approach
A non-equilibrium steady state thermodynamics to describe shear flows is
developed using a canonical distribution approach. We construct a canonical
distribution for shear flow based on the energy in the moving frame using the
Lagrangian formalism of the classical mechanics. From this distribution we
derive the Evans-Hanley shear flow thermodynamics, which is characterized by
the first law of thermodynamics relating infinitesimal
changes in energy , entropy and shear rate with kinetic
temperature . Our central result is that the coefficient is given by
Helfand's moment for viscosity. This approach leads to thermodynamic stability
conditions for shear flow, one of which is equivalent to the positivity of the
correlation function of . We emphasize the role of the external work
required to sustain the steady shear flow in this approach, and show
theoretically that the ensemble average of its power must be
non-negative. A non-equilibrium entropy, increasing in time, is introduced, so
that the amount of heat based on this entropy is equal to the average of
. Numerical results from non-equilibrium molecular dynamics simulation
of two-dimensional many-particle systems with soft-core interactions are
presented which support our interpretation.Comment: 23 pages, 7 figure
Localized behavior in the Lyapunov vectors for quasi-one-dimensional many-hard-disk systems
We introduce a definition of a "localization width" whose logarithm is given
by the entropy of the distribution of particle component amplitudes in the
Lyapunov vector. Different types of localization widths are observed, for
example, a minimum localization width where the components of only two
particles are dominant. We can distinguish a delocalization associated with a
random distribution of particle contributions, a delocalization associated with
a uniform distribution and a delocalization associated with a wave-like
structure in the Lyapunov vector. Using the localization width we show that in
quasi-one-dimensional systems of many hard disks there are two kinds of
dependence of the localization width on the Lyapunov exponent index for the
larger exponents: one is exponential, and the other is linear. Differences, due
to these kinds of localizations also appear in the shapes of the localized
peaks of the Lyapunov vectors, the Lyapunov spectra and the angle between the
spatial and momentum parts of the Lyapunov vectors. We show that the Krylov
relation for the largest Lyapunov exponent as a
function of the density is satisfied (apart from a factor) in the same
density region as the linear dependence of the localization widths is observed.
It is also shown that there are asymmetries in the spatial and momentum parts
of the Lyapunov vectors, as well as in their and -components.Comment: 41 pages, 21 figures, Manuscript including the figures of better
quality is available from http://www.phys.unsw.edu.au/~gary/Research.htm
Parameter estimation for compact binary coalescence signals with the first generation gravitational-wave detector network
Compact binary systems with neutron stars or black holes are one of the most promising sources for ground-based gravitational-wave detectors. Gravitational radiation encodes rich information about source physics; thus parameter estimation and model selection are crucial analysis steps for any detection candidate events. Detailed models of the anticipated waveforms enable inference on several parameters, such as component masses, spins, sky location and distance, that are essential for new astrophysical studies of these sources. However, accurate measurements of these parameters and discrimination of models describing the underlying physics are complicated by artifacts in the data, uncertainties in the waveform models and in the calibration of the detectors. Here we report such measurements on a selection of simulated signals added either in hardware or software to the data collected by the two LIGO instruments and the Virgo detector during their most recent joint science run, including a âblind injectionâ where the signal was not initially revealed to the collaboration. We exemplify the ability to extract information about the source physics on signals that cover the neutron-star and black-hole binary parameter space over the component mass range 1âMââ25âMâ and the full range of spin parameters. The cases reported in this study provide a snapshot of the status of parameter estimation in preparation for the operation of advanced detectors
Lamotrigine versus inert placebo in the treatment of borderline personality disorder: study protocol for a randomized controlled trial and economic evaluation
Background: People with borderline personality disorder (BPD) experience rapid and distressing changes in mood, poor social functioning and have high rates of suicidal behaviour. Several small scale studies suggest that mood stabilizers may produce short-term reductions in symptoms of BPD, but have not been large enough to fully examine clinical and cost-effectiveness. Methods/Design: A two parallel-arm, placebo controlled randomized trial of usual care plus either lamotrigine or an inert placebo for people aged over 18 who are using mental health services and meet diagnostic criteria for BPD. We will exclude people with comorbid bipolar affective disorder or psychosis, those already taking a mood stabilizer, those who speak insufficient English to complete the baseline assessment and women who are pregnant or contemplating becoming pregnant. Those meeting inclusion criteria and provide written informed consent will be randomized to up to 200mg of lamotrigine per day or an inert placebo (up to 400mg if taking combined oral contraceptives).Participants will be randomized via a remote web-based system using permuted stacked blocks stratified by study centre, severity of personality disorder, and level of bipolarity. Follow-up assessments will be conducted by masked researchers 12, 24 weeks, and 52 weeks after randomization. The primary outcome is the Zanarini Rating Scale for Borderline Personality Disorder (ZAN-BPD). The secondary outcomes are depressive symptoms, deliberate self-harm, social functioning, health-related quality of life, resource use and costs, side effects of treatment, adverse events and withdrawal of trial medication due to adverse effects. The main analyses will use intention to treat without imputation of missing data. The economic evaluation will take an NHS/Personal Social Services perspective. A cost-utility analysis will compare differences in total costs and differences in quality of life using QALYs derived from the EQ-5D. Discussion: The evidence base for the use of pharmacological treatments for people with borderline personality disorder is poor. In this trial we will examine the clinical and cost-effectiveness of lamotrigine to assess what if any impact offering this has on peoplesâ mental health, social functioning, and use of other medication and other resources. Trial registration: Current Controlled Trials ISRCTN90916365 (registered 01/08/2012
In their own words: qualitative study of high-utilising primary care patients with medically unexplained symptoms
Search for long-lived gravitational-wave transients coincident with long gamma-ray bursts
Long gamma-ray bursts (GRBs) have been linked to extreme core-collapse supernovae from massive stars. Gravitational waves (GW) offer a probe of the physics behind long GRBs. We investigate models of long-lived (~10â1000 s) GW emission associated with the accretion disk of a collapsed star or with its protoneutron star remnant. Using data from LIGOâs fifth science run, and GRB triggers from the Swift experiment, we perform a search for unmodeled long-lived GW transients. Finding no evidence of GW emission, we place 90% confidence-level upper limits on the GW fluence at Earth from long GRBs for three waveforms inspired by a model of GWs from accretion disk instabilities. These limits range from FtoFcm-2, depending on the GRB and on the model, allowing us to probe optimistic scenarios of GW production out to distances as far as = 33 Mpc. Advanced detectors are expected to achieve strain sensitivities 10x better than initial LIGO, potentially allowing us to probe the engines of the nearest long GRBs
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