157 research outputs found

    Linear theory and violent relaxation in long-range systems: a test case

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    In this article, several aspects of the dynamics of a toy model for longrange Hamiltonian systems are tackled focusing on linearly unstable unmagnetized (i.e. force-free) cold equilibria states of the Hamiltonian Mean Field (HMF). For special cases, exact finite-N linear growth rates have been exhibited, including, in some spatially inhomogeneous case, finite-N corrections. A random matrix approach is then proposed to estimate the finite-N growth rate for some random initial states. Within the continuous, N→∞N \rightarrow \infty, approach, the growth rates are finally derived without restricting to spatially homogeneous cases. All the numerical simulations show a very good agreement with the different theoretical predictions. Then, these linear results are used to discuss the large-time nonlinear evolution. A simple criterion is proposed to measure the ability of the system to undergo a violent relaxation that transports it in the vicinity of the equilibrium state within some linear e-folding times

    Skills-based intervention to enhance collaborative decision-making: systematic adaptation and open trial protocol for veterans with psychosis

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    Background: Collaborative decision-making is an innovative decision-making approach that assigns equal power and responsibility to patients and providers. Most veterans with serious mental illnesses like schizophrenia want a greater role in treatment decisions, but there are no interventions targeted for this population. A skills-based intervention is promising because it is well-aligned with the recovery model, uses similar mechanisms as other evidence-based interventions in this population, and generalizes across decisional contexts while empowering veterans to decide when to initiate collaborative decision-making. Collaborative Decision Skills Training (CDST) was developed in a civilian serious mental illness sample and may fill this gap but needs to undergo a systematic adaptation process to ensure fit for veterans. Methods: In aim 1, the IM Adapt systematic process will be used to adapt CDST for veterans with serious mental illness. Veterans and Veteran’s Affairs (VA) staff will join an Adaptation Resource Team and complete qualitative interviews to identify how elements of CDST or service delivery may need to be adapted to optimize its effectiveness or viability for veterans and the VA context. During aim 2, an open trial will be conducted with veterans in a VA Psychosocial Rehabilitation and Recovery Center (PRRC) to assess additional adaptations, feasibility, and initial evidence of effectiveness. Discussion: This study will be the first to evaluate a collaborative decision-making intervention among veterans with serious mental illness. It will also contribute to the field’s understanding of perceptions of collaborative decision-making among veterans with serious mental illness and VA clinicians, and result in a service delivery manual that may be used to understand adaptation needs generally in VA PRRCs. Trial registration: ClinicalTrials.gov Identifier: NCT0432494

    Case study in six sigma methadology : manufacturing quality improvement and guidence for managers

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    This article discusses the successful implementation of Six Sigma methodology in a high precision and critical process in the manufacture of automotive products. The Six Sigma define–measure–analyse–improve–control approach resulted in a reduction of tolerance-related problems and improved the first pass yield from 85% to 99.4%. Data were collected on all possible causes and regression analysis, hypothesis testing, Taguchi methods, classification and regression tree, etc. were used to analyse the data and draw conclusions. Implementation of Six Sigma methodology had a significant financial impact on the profitability of the company. An approximate saving of US$70,000 per annum was reported, which is in addition to the customer-facing benefits of improved quality on returns and sales. The project also had the benefit of allowing the company to learn useful messages that will guide future Six Sigma activities

    Epidemic space

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    The aim of this article is to highlight the importance of 'spatiality' in understanding the materialization of risk society and cultivation of risk sensibilities. More specifically it provides a cultural analysis of pathogen virulence (as a social phenomenon) by means of tracing and mapping the spatial flows that operate in the uncharted zones between the microphysics of infection and the macrophysics of epidemics. It will be argued that epidemic space consists of three types of forces: the vector, the index and the vortex. It will draw on Latour's Actor Network Theory to argue that epidemic space is geared towards instability when the vortex (of expanding associations and concerns) displaces the index (of finding a single cause)

    A qualitative emancipatory inquiry into relationships between people with mental disorders and health professionals

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    Introduction: A therapeutic alliance with people is essential for the efficacy of treatments. However, the traditional paternalistic values of the Mediterranean society may be incompatible with patient autonomy. Aim: To explore the therapeutic relationship from the perspective of people diagnosed with mental disorders with health professionals, including nurses. Methods: This emancipatory research was performed through focus groups, with people with mental disorders who had a variety of diagnoses and experiences of acute and community‐based mental health services and other healthcare services. Data were analysed using the content analysis method. Results: Four main themes emerged: stereotypes and prejudice; quality of interactions and treatment; emotional and behavioural impacts; and demands. Discussion: According to the participants' descriptions, health professionals are not exempt from prejudice against persons with psychiatric diagnoses. They reported experiencing abuse of power, malpractice, and overmedication. Thus, in the Mediterranean culture, professional attitudes may represent a barrier for an appropriate therapeutic alliance, and people with mental disorders do not feel involved in making decisions about their health. Implications for practice: Knowing how people with mental disorders perceive their interactions with health professionals and the effects is necessary to move the care model towards more symmetric relationships that facilitate a therapeutic alliance

    Skills-based intervention to enhance collaborative decision-making: systematic adaptation and open trial protocol for veterans with psychosis

    Get PDF
    Background Collaborative decision-making is an innovative decision-making approach that assigns equal power and responsibility to patients and providers. Most veterans with serious mental illnesses like schizophrenia want a greater role in treatment decisions, but there are no interventions targeted for this population. A skills-based intervention is promising because it is well-aligned with the recovery model, uses similar mechanisms as other evidence-based interventions in this population, and generalizes across decisional contexts while empowering veterans to decide when to initiate collaborative decision-making. Collaborative Decision Skills Training (CDST) was developed in a civilian serious mental illness sample and may fill this gap but needs to undergo a systematic adaptation process to ensure fit for veterans. Methods In aim 1, the IM Adapt systematic process will be used to adapt CDST for veterans with serious mental illness. Veterans and Veteran’s Affairs (VA) staff will join an Adaptation Resource Team and complete qualitative interviews to identify how elements of CDST or service delivery may need to be adapted to optimize its effectiveness or viability for veterans and the VA context. During aim 2, an open trial will be conducted with veterans in a VA Psychosocial Rehabilitation and Recovery Center (PRRC) to assess additional adaptations, feasibility, and initial evidence of effectiveness. Discussion This study will be the first to evaluate a collaborative decision-making intervention among veterans with serious mental illness. It will also contribute to the field’s understanding of perceptions of collaborative decision-making among veterans with serious mental illness and VA clinicians, and result in a service delivery manual that may be used to understand adaptation needs generally in VA PRRCs

    Anthroposophic therapy for chronic depression: a four-year prospective cohort study

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    BACKGROUND: Depressive disorders are common, cause considerable disability, and do not always respond to standard therapy (psychotherapy, antidepressants). Anthroposophic treatment for depression differs from ordinary treatment in the use of artistic and physical therapies and special medication. We studied clinical outcomes of anthroposophic therapy for depression. METHODS: 97 outpatients from 42 medical practices in Germany participated in a prospective cohort study. Patients were aged 20–69 years and were referred to anthroposophic therapies (art, eurythmy movement exercises, or rhythmical massage) or started physician-provided anthroposophic therapy (counselling, medication) for depression: depressed mood, at least two of six further depressive symptoms, minimum duration six months, Center for Epidemiological Studies Depression Scale, German version (CES-D, range 0–60 points) of at least 24 points. Outcomes were CES-D (primary outcome) and SF-36 after 3, 6, 12, 18, 24, and 48 months. Data were collected from July 1998 to March 2005. RESULTS: Median number of art/eurythmy/massage sessions was 14 (interquartile range 12–22), median therapy duration was 137 (91–212) days. All outcomes improved significantly between baseline and all subsequent follow-ups. Improvements from baseline to 12 months were: CES-D from mean (standard deviation) 34.77 (8.21) to 19.55 (13.12) (p < 0.001), SF-36 Mental Component Summary from 26.11 (7.98) to 39.15 (12.08) (p < 0.001), and SF-36 Physical Component Summary from 43.78 (9.46) to 48.79 (9.00) (p < 0.001). All these improvements were maintained until last follow-up. At 12-month follow-up and later, 52%–56% of evaluable patients (35%–42% of all patients) were improved by at least 50% of baseline CES-D scores. CES-D improved similarly in patients not using antidepressants or psychotherapy during the first six study months (55% of patients). CONCLUSION: In outpatients with chronic depression, anthroposophic therapies were followed by long-term clinical improvement. Although the pre-post design of the present study does not allow for conclusions about comparative effectiveness, study findings suggest that the anthroposophic approach, with its recourse to non-verbal and artistic exercising therapies can be useful for patients motivated for such therapies

    Towards a resolution of some outstanding issues in transitive research: an empirical test on middle childhood

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    Transitive Inference (deduce B > D from B > C and C > D) can help us to understand other areas of sociocognitive development. Across three experiments, learning, memory, and the validity of two transitive paradigms were investigated. In Experiment 1 (N = 121), 7-year-olds completed a three-term nontraining task or a five-term task requiring extensive-training. Performance was superior on the three-term task. Experiment 2 presented 5–10-year-olds with a new five-term task, increasing learning opportunities without lengthening training (N = 71). Inferences improved, suggesting children can learn five-term series rapidly. Regarding memory, the minor (CD) premise was the best predictor of BD-inferential performance in both task-types. However, tasks exhibited different profiles according to associations between the major (BC) premise and BD inference, correlations between the premises, and the role of age. Experiment 3 (N = 227) helped rule out the possible objection that the above findings simply stemmed from three-term tasks with real objects being easier to solve than computer-tasks. It also confirmed that, unlike for five-term task (Experiments 1 & 2), inferences on three-term tasks improve with age, whether the age range is wide (Experiment 3) or narrow (Experiment 2). I conclude that the tasks indexed different routes within a dual-process conception of transitive reasoning: The five-term tasks indexes Type 1 (associative) processing, and the three-term task indexes Type 2 (analytic) processing. As well as demonstrating that both tasks are perfectly valid, these findings open up opportunities to use transitive tasks for educability, to investigate the role of transitivity in other domains of reasoning, and potentially to benefit the lived experiences of persons with developmental issues
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