Quasi-elastic and inelastic inclusive electron scattering from an oxygen jet target

The results of an experiment on inclusive electron scattering from an oxygen jet target, performed in a wide range of energy and momentum transfer covering both quasi-elastic and $\Delta$(1232) resonance regions, are reported. In the former region the theoretical predictions, obtained including effects of nucleon-nucleon correlations in both initial and final states, give a good description of the experimental data. In the inelastic region a broadening as well as a damping of the resonant part of the cross section with respect to the free nucleon case is observed. The need of more detailed calculations including nuclear structure effects on the electroproduction cross section of nucleon resonances is highlighted.Comment: to appear in Nucl. Phys.

Determination of Matter Surface Distribution of Neutron-rich Nuclei

We demonstrate that the matter density distribution in the surface region is determined well by the use of the relatively low-intensity beams that become available at the upcoming radioactive beam facilities. Following the method used in the analyses of electron scattering, we examine how well the density distribution is determined in a model-independent way by generating pseudo data and by carefully applying statistical and systematic error analyses. We also study how the determination becomes deteriorated in the central region of the density, as the quality of data decreases. Determination of the density distributions of neutron-rich nuclei is performed by fixing parameters in the basis functions to the neighboring stable nuclei. The procedure allows that the knowledge of the density distributions of stable nuclei assists to strengthen the determination of their unstable isotopes.Comment: 41 pages, latex, 27 figure

Exchange flow between open water and floating vegetation

This study describes the exchange flow between a region with open water and a region with a partial-depth porous obstruction, which represents the thermally-driven exchange that occurs between open water and floating vegetation. The partial-depth porous obstruction represents the root layer, which does not penetrate to the bed. Initially, a vertical wall separates the two regions, with fluid of higher density in the obstructed region and fluid of lower density in the open region. This density difference represents the influence of differential solar heating due to shading by the vegetation. For a range of root density and root depths, the velocity distribution is measured in the lab using PIV. When the vertical wall is removed, the less dense water flows into the obstructed region at the surface. This surface flow bifurcates into two layers, one flowing directly through the root layer and one flowing beneath the root layer. A flow directed out of the vegetated region occurs at the bed. A model is developed that predicts the flow rates within each layer based on energy considerations. The experiments and model together suggest that at time- and length-scales relevant to the field, the flow structure for any root layer porosity approaches that of a fully blocked layer, for which the exchange flow occurs only beneath the root layer.National Science Foundation (U.S.) (grant EAR0509658

Proton Spin Structure in the Resonance Region

We have examined the spin structure of the proton in the region of the nucleon resonances (1.085 GeV < W < 1.910 GeV) at an average four momentum transfer of Q^2 = 1.3 GeV^2. Using the Jefferson Lab polarized electron beam, a spectrometer, and a polarized solid target, we measured the asymmetries A_parallel and A_perp to high precision, and extracted the asymmetries A_1 and A_2, and the spin structure functions g_1 and g_2. We found a notably non-zero A_perp, significant contributions from higher-twist effects, and only weak support for polarized quark--hadron duality.Comment: 6 pages, 4 figures, REVTeX4, similar to PRL submission, plots colorized and appenix added, v3: minor edit, matches PR

Integrating acute stroke telemedicine consultations into specialists' usual practice: a qualitative analysis comparing the experience of Australia and the United Kingdom

Stroke telemedicine can reduce healthcare inequities by increasing access to specialists. Successful telemedicine networks require specialists adapting clinical practice to provide remote consultations. Variation in experiences of specialists between different countries is unknown. To support future implementation, we compared perceptions of Australian and United Kingdom specialists providing remote acute stroke consultations. Specialist participants were identified using purposive sampling from two new services: Australia's Victorian Stroke Telemedicine Program (n = 6; 2010-13) and the United Kingdom's Cumbria and Lancashire telestroke network (n = 5; 2010-2012). Semi-structured interviews were conducted pre- and post-implementation, recorded and transcribed verbatim. Deductive thematic and content analysis (NVivo) was undertaken by two independent coders using Normalisation Process Theory to explore integration of telemedicine into practice. Agreement between coders was M = 91%, SD = 9 and weighted average κ = 0.70. Cross-cultural similarities and differences were found. In both countries, specialists described old and new consulting practices, the purpose and value of telemedicine systems, and concerns regarding confidence in the assessment and diagnostic skills of unknown colleagues requesting telemedicine support. Australian specialists discussed how remote consultations impacted on usual roles and suggested future improvements, while United Kingdom specialists discussed system governance, policy and procedures. Australian and United Kingdom specialists reported telemedicine required changes in work practice and development of new skills. Both groups described potential for improvements in stroke telemedicine systems with Australian specialists more focused on role change and the United Kingdom on system governance issues. Future research should examine if cross-cultural variation reflects different models of care and extends to other networks

Motivational Interviewing Post-Stroke: An Analysis of Stroke Survivors' Concerns and Adjustment

Our earlier research demonstrated that participation in four sessions of motivational interviewing (MI) early post-stroke has a positive impact on stroke survivors' mood. However, the theoretical underpinnings of MI in supporting adjustment (rather than its traditional use in supporting behavior change) require clarification. This article describes a content analysis of MI transcripts for 10 participants in our previous study, to identify the focus of discussions (patient "concerns") and potential effective components of our MI approach. Patients' post-stroke concerns were shown in 16 categories, including frustration, family impact, and getting well. There was a pattern of change discourse across sessions: "Sustain talk" (reasons for not changing) reduced from Session 1 onward, "change talk" (intent to change) increased then reduced, and "change expressed" (changes achieved) increased from Sessions 1 to 4. MI facilitates healthy adjustment post-stroke in some patients, in turn affecting mood, but clarification of how this effect is achieved requires further exploration

Fidelity to a motivational interviewing intervention for those with post-stroke aphasia : A small-scale feasibility study

Objective: Depression after stroke is common, and talk-based psychological therapies can be a useful intervention. While a third of stroke survivors will experience communication difficulties impeding participation in talk-based therapies, little guidance exists to guide delivery for those with aphasia. We need to understand how to adapt talk-based therapies in the presence of aphasia. This study aimed to explore the feasibility of motivational interviewing (MI) in people with post-stroke aphasia. Methods: In a small-scale feasibility study, consecutive patients admitted to an acute stroke ward were screened for eligibility. People with moderate to severe aphasia were eligible. Those consenting received an intervention consisting of up to eight MI sessions delivered twice per week over four weeks. Sessions were modified using aids and adaptations for aphasia. Session quality was measured using the Motivational Interviewing Skills Code (MISC) to assess MI fidelity. Results: Three consenting patients identified early post-stroke took part; one male and two females ages ranging between 40s and 80s. Participants attended between five and eight MI sessions over four weeks. Aids and adaptations included visual cues, rating scales, and modified reflections incorporating verbal and non-verbal behaviors. Sessions were tailored to individual participant need. Threshold MISC ratings could be achieved for all participants however, ratings were reduced when aids and adaptations were not used. Discussion: This small-scale feasibility study suggests that it is feasible to adapt MI for people with moderate to severe post-stroke aphasia. These findings merit further exploration of adapted MI as an intervention for this patient group

Barriers and facilitators to implementation of the free water protocol in the acute stroke unit setting: a mixed methods systematic review

Free water protocols (FWP) give patients at risk of aspiration the option to drink water between meals. Evidence is lacking about their use in acute stroke care. This systematic review evaluated the literature about barriers and facilitators to FWP implementation in acute stroke unit settings. Electronic databases and grey literature sources were systematically searched, eligible studies were critically appraised, and data extracted and mapped onto the Consolidated Framework for Implementation Research (CFIR). The results are presented in a narrative synthesis. Five studies were identified for inclusion: Two qualitative studies, 1 mixed method study, 1 randomised controlled trial and 1 pilot cohort study. Barriers and facilitators to implementation were identified across the 5 CFIR domains. Key barriers were a lack of evidence base and a standard protocol, trying to adapt and deliver a protocol designed for a different setting, complexity of patient selection and FWP design, culture of risk aversion, nursing staff availability and skills to deliver the FWP, and a greater use of agency nurses and transient workforce. Key facilitators were the existence of national guidance for research into its use, implementation of oral care protocols prior to FWP implementation, the unique characteristics of the acute stroke setting, leadership and modelling by senior clinicians, interdisciplinary working and accountability for roles and responsibilities for each discipline, regular communication and ongoing education, and involving patients in decision making and implementation. The findings of this review will guide the data collection of a feasibility study of the FWP in acute stroke

The effects of a dialogue-based intervention to promote psychosocial well-being after stroke: a randomized controlled trial

Objective: To evaluate the effect of a dialogue-based intervention targeting psychosocial well-being at 12 months post-stroke. Design: Multicenter, prospective, randomized, assessor-blinded, controlled trial with two parallel groups. Setting: Community. Subjects: Three-hundred and twenty-two adults (⩾18 years) with stroke within the last four weeks were randomly allocated into intervention group (n = 166) or control group (n = 156). Interventions: The intervention group received a dialogue-based intervention to promote psychosocial well-being, comprising eight individual 1–1½ hour sessions delivered during the first six months post-stroke. Main measures: The primary outcome measure was the General Health Questionnaire-28 (GHQ-28). Secondary outcome measures included the Stroke and Aphasia Quality of Life Scale-39g, the Sense of Coherence scale, and the Yale Brown single-item questionnaire. Results: The mean (SD) age of the participants was 66.8 (12.1) years in the intervention group and 65.7 (13.3) years in the control group. At 12 months post-stroke, the mean (SE) GHQ-28 score was 20.6 (0.84) in the intervention group and 19.9 (0.85) in the control group. There were no between-group differences in psychosocial well-being at 12 months post-stroke (mean difference: −0.74, 95% confidence interval (CI): −3.08, 1.60). The secondary outcomes showed no statistically significant between-group difference in health-related quality of life, sense of coherence, or depression at 12 months. Conclusion: The results of this trial did not demonstrate lower levels of emotional distress and anxiety or higher levels of health-related quality of life in the intervention group (dialogue-based intervention) as compared to the control group (usual care) at 12 months post-stroke