4,963 research outputs found
Evaluation of techniques for removal of spacecraft contaminants from activated carbon
Alternative techniques for the regeneration of carbon contaminated with various spacecraft contaminants were evaluated. Four different modes of regeneration were evaluated: (1) thermal desorption via vacuum, (2) thermal desorption via nitrogen purge, (3) in-situ catalytic oxidation of adsorbed contaminants, and (4) in-situ non-catalytic oxidation of adsorbed contaminants
Contaminant removal from enclosed atmospheres by regenerable adsorbents
A system for removing contaminants from spacecraft atmospheres was studied, which utilizes catalyst-impregnated activated carbon followed by in-situ regeneration by low-temperature catalytic oxidation of the adsorbed contaminants. Platinum was deposited on activated carbon by liquid phase impregnation with chloroplatinic acid, followed by drying and high-temperature reduction. Results were obtained for the seven selected spacecraft contaminants by means of three experimental test systems. The results indicate that the contaminants could be removed by oxidation with very little loss in adsorptive capacity. The advantages of a catalyst-impregnated carbon for oxidative regeneration are found to be significant enough to warrent its use
Adjustment with aphasia after stroke: study protocol for a pilot feasibility randomised controlled trial for SUpporting wellbeing through PEeR Befriending (SUPERB)
Background: Despite the high prevalence of mood problems after stroke, evidence on effective interventions particularly for those with aphasia is limited. There is a pressing need to systematically evaluate interventions aiming to improve wellbeing for people with stroke and aphasia. This study aims to evaluate the feasibility of a peer-befriending intervention.
Methods/design: SUPERB is a single blind, parallel group feasibility trial of peer befriending for people with aphasia post-stroke and low levels of psychological distress. The trial includes a nested qualitative study and pilot economic evaluation and it compares usual care (n = 30) with usual care + peer befriending (n = 30). Feasibility outcomes include proportion screened who meet criteria, proportion who consent, rate of consent, number of missing/incomplete data on outcome measures, attrition rate at follow-up, potential value of conducting main trial using value of information analysis (economic evaluation), description of usual care, and treatment fidelity of peer befriending. Assessments and outcome measures (mood, wellbeing, communication, and social participation) for participants and significant others will be administered at baseline, with outcome measures re-administered at 4 and 10 months post-randomisation. Peer befrienders will complete outcome measures before training and after they have completed two cycles of befriending. The qualitative study will use semi-structured interviews of purposively sampled participants (n = 20) and significant others (n = 10) from both arms of the trial, and all peer befrienders to explore the acceptability of procedures and experiences of care. The pilot economic evaluation will utilise the European Quality of life measure (EQ-5D-5 L) and a stroke-adapted version of the Client Service Receipt Inventory (CSRI).
Discussion: This study will provide information on feasibility outcomes and an initial indication of whether peer befriending is a suitable intervention to explore further in a definitive phase III randomised controlled trial.
Trial registration: ClinicalTrials.gov identifier NCT02947776, registered 28th October 2016
SWAS and Arecibo observations of H2O and OH in a diffuse cloud along the line-of-sight to W51
Observations of W51 with the Submillimeter Wave Astronomy Satellite (SWAS)
have yielded the first detection of water vapor in a diffuse molecular cloud.
The water vapor lies in a foreground cloud that gives rise to an absorption
feature at an LSR velocity of 6 km/s. The inferred H2O column density is
2.5E+13 cm-2. Observations with the Arecibo radio telescope of hydroxyl
molecules at ten positions in W51 imply an OH column density of 8E+13 cm-2 in
the same diffuse cloud. The observed H2O/OH ratio of ~ 0.3 is significantly
larger than an upper limit derived previously from ultraviolet observations of
the similar diffuse molecular cloud lying in front of HD 154368. The observed
variation in H2O/OH likely points to the presence in one or both of these
clouds of a warm (T > 400) gas component in which neutral-neutral reactions are
important sources of OH and/or H2O.Comment: 15 pages (AASTeX) including 4 (eps) figures. To appear in the
Astrophysical Journa
Temperature perturbation model of the opto-galvanic effect in CO2-laser discharges
A detailed discharge model of the opto-galvanic effect in molecular laser gas mixtures is developed based on the temperature perturbation or discharge cooling mechanism of Smith and Brooks (1979). Excellent agreement between the model and experimental results in CO2 laser gas mixtures is obtained. The model should be applicable to other molecular systems where the OGE is being used for laser stabilisation and as a spectroscopic tool
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Blinding participants and assessors in a feasibility randomised controlled trial of peer-befriending for people with aphasia post-stroke
Background and aims: In behavioural interventions, blinding participants to intervention versus control conditions is problematic, as is blinding assessors to participants’ group allocation. When participants are provided with information about the intervention to be tested, they will know whether they are in the intervention or the control arm of the study. This is particularly problematic in psychological interventions where people who may already be distressed or anxious are likely to become even more distressed when they realise they are in the control arm of a study. To minimise potential threats to validity and maintain lack of bias, we took a number of steps in the SUpporting well-being through PEeR-Befriending (SUPERB) feasibility trial for people with aphasia to ensure blinding. This presentation will report on these steps and evaluate their effectiveness. Methods: SUPERB is a single blind, mixed methods, parallel group phase II randomised controlled trial (RCT) comparing usual care+peer-befriending (n = 30) versus usual care (n = 30), starting at discharge from hospital. Little is known about what usual care for psychological support after stroke-aphasia constitutes, and this study will document the services the participants receive in their area for both groups. A modified two-stage consent design has been adopted (Campbell, Peters, Grant, Quilty, & Dieppe, 2005; Torgerson & Roland, 1998), as highlighted in the Medical Research Council framework for complex interventions (Craig et al., 2008). In the first stage, all participants consent to take part in a study on adjustment post-stroke and have their data collected at three time points (i.e., baseline, 4 months, and 10 months). They know they may be compared to other people in the study receiving different packages of care, but are blind to the fact that the study tests a specific intervention (peer-befriending). Following baseline assessments, participants are randomised to either usual care+peer-befriending or usual care. At this point, a second stage consent to take part in the intervention is completed with those participants allocated to the peer-befriending arm. Rate of consent at both stages is monitored. Blinded researchers (assessors) complete assessments for both groups at 4 months and 10 months. Strategies to maintain blinding of assessors include the following: the use of scripts during assessments and asking the participants not to reveal what care they have received; unblinded researcher organising post-randomisation appointments, so that assessors cannot become unblinded by partners/carers of people with aphasia revealing information; and management of the work environment (separate office space, different telephones, and no physical or electronic access to sensitive data). Instances of unblinding are recorded. Results: The trial is currently underway. Thirty-eight of 60 participants have been recruited and 27 have been randomised. The two-stage consent process has been largely successful. No instances of unblinding by participants or researchers have been recorded. Near misses (n = 4) have been recorded for the blinded researchers. These are unrelated to the assessments with participants but rather workplace factors (e.g., use of email, shared calendars, and overhearing telephone conversations). Conclusions: Blinding of participants and researchers is critical to the success of a RCT. This paper raises and discusses a range of processes including a modified two-stage consent process and careful preparation and monitoring of participants, researchers, and workplace factors – which are all important steps to reducing the possibility of unblinding
SUpporting wellbeing through PEeR-Befriending (SUPERB) feasibility trial: fidelity of peer-befriending for people with aphasia.
Objective To evaluate systematically the fidelity of a peer-befriending intervention for people with aphasia.
Design SUpporting wellbeing through Peer-befriending (SUPERB) was a feasibility randomised controlled trial comparing usual care to usual care +peer-befriending. This paper reports on the fidelity of all intervention aspects (training and supervision of providers/befrienders; intervention visits) which was evaluated across all areas of the Behaviour Change Consortium framework.
Setting Community.
Participants People with aphasia early poststroke and low levels of distress, randomised to the intervention arm of the trial (n=28); 10 peer-befrienders at least 1-year poststroke.
Intervention Peer-befrienders were trained (4–6 hours); and received regular supervision (monthly group while actively befriending, and one-to-one as and when needed) in order to provide six 1-hour peer-befriending visits over 3 months.
Main measures Metrics included number and length of training, supervision sessions and visits. All training and supervision sessions and one (of six) visits per pair were rated against fidelity checklists and evaluated for inter-rater and intrarater reliability (Gwets AC1 agreement coefficient). Per-cent adherence to protocol was evaluated.
Results All peer-befrienders received 4–6 hours training over 2–3 days as intended. There were 25 group supervision sessions with a median number attended of 14 (IQR=8–18). Twenty-six participants agreed (92.8%) to the intervention and 21 (80.8%) received all six visits (median visit length 60 min). Adherence was high for training (91.7%–100%) and supervision (83%–100%) and moderate-to-high for befriending visits (66.7%–100%). Where calculable, inter-rater and intrarater reliability was high for training and supervision (Gwets AC1 >0.90) and moderate-to-high for intervention visits (Gwets AC1 0.44–1.0).
Conclusion Planning of fidelity processes at the outset of the trial and monitoring throughout was feasible and ensured good-to-high fidelity for this peer-befriending intervention. The results permit confidence in other findings from the SUPERB trial
“For them and for me”: a qualitative exploration of peer befrienders’ experiences supporting people with aphasia in the SUPERB feasibility trial
Peer-befriending, where support is offered by someone with shared lived experience, is an intervention that may facilitate successful adjustment in people experiencing post-stroke aphasia. This paper explores the experiences of the peer-befrienders. People with aphasia were recruited as peer-befrienders within the SUPERB trial investigating befriending for people with post-stroke aphasia. The intervention comprised six visits over three months. Peer-befrienders were matched with at least one befriendee and received training and ongoing supervision. They were invited to participate in in-depth interviews which were analysed using framework analysis. All 10 befrienders participated in interviews, reporting on 19 matches. Seven main themes emerged: content of the sessions; befriender-befriendee relationship; negotiating the visits; handling boundaries and endings; positive impact of the befriending for befrienders and befriendees; and beliefs about the nature and value of peer support. While befrienders described challenges, such as negotiating journeys and witnessing distress, the role was perceived as a "secure challenge" due to the support and training received. Befrienders perceived the role as enjoyable and rewarding, and felt they were making a positive difference. They were unanimous in believing that people with aphasia can offer unique and valuable support to others with aphasia. ClinicalTrials.gov identifier NCT02947776, registered 28th October 2016.Implications for rehabilitationPeople with lived experience of stroke and aphasia were able to offer emotional and social peer support to others with aphasia within the SUPERB trial.Although there were challenges, peer befrienders perceived the role as rewarding and satisfying.Peer befrienders valued the training and ongoing supervision and support they received to deliver the intervention.It is recommended that rehabilitation professionals considering offering peer-befriending schemes provide training and ongoing supervision to support peer-befrienders fulfil their role, as well as practical support with, e.g., arranging visits
“Loneliness can also kill:” a qualitative exploration of outcomes and experiences of the SUPERB peer-befriending scheme for people with aphasia and their significant others
People with aphasia post-stroke are at risk for depression and social isolation. Peer-befriending from someone with similar experiences may promote wellbeing and provide support. This paper explored the views of people with aphasia and their significant others about peer-befriending. We conducted a qualitative study within a feasibility trial (SUPERB) on peer-befriending for people with post-stroke aphasia and low levels of distress. Of the 28 participants randomised to the intervention, semi-structured in-depth interviews were conducted with 10 purposively selected people with aphasia (at both 4- and 10-months post-randomisation) and five of their significant others (at 4-months). Interviews were analysed using Framework Analysis. Participants and their significant others were positive about peer-befriending and identified factors which influenced their experience: the befrienders' personal experience of stroke and aphasia, their character traits and the resulting rapport these created, the conversation topics they discussed and settings they met in, and the logistics of befriending, including planning visits and negotiating their end. Interviewees also made evaluative comments about the befriending scheme. Peer-befriending was an acceptable intervention. Benefits for emotional wellbeing and companionship were reported. The shared experience in the befriending relationship was highly valued.Implications for RehabilitationThe lived experience of stroke and aphasia of befrienders was highly valued by people with aphasia receiving peer-befriending.Training, regular supervision, and support for befrienders with practicalities such as organising visits ensured the befriending scheme was perceived as straightforward and acceptable by befriendees.Those receiving peer-befriending would recommend it to others; they found it beneficial, especially in terms of emotional wellbeing and companionship
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