146 research outputs found
Investigation into the recovery of function after different types of injury and repair of peripheral nerve: a comparison between non-diabetic and STZ diabetic rats
Implementation of the Crisis Resolution Team model in adult mental health settings: a systematic review.
Crisis Resolution Teams (CRTs) aim to offer an alternative to hospital admission during mental health crises, providing rapid assessment, home treatment, and facilitation of early discharge from hospital. CRTs were implemented nationally in England following the NHS Plan of 2000. Single centre studies suggest CRTs can reduce hospital admissions and increase service users' satisfaction: however, there is also evidence that model implementation and outcomes vary considerably. Evidence on crucial characteristics of effective CRTs is needed to allow team functioning to be optimised. This review aims to establish what evidence, if any, is available regarding the characteristics of effective and acceptable CRTs
Belousov-Zhabotinsky reaction in liquid marbles
In BelousovâZhabotinsky (BZ) type reactions, chemical oxidation waves can be exploited to produce reaction-diffusion processors. This paper reports on a new method of encapsulating BZ solution in a powder coating of either polyethylene (PE) or polytetrafluoroethylene (PTFE), to produce BZ liquid marbles (LMs). BZ LMs have solid-liquid interfaces compared to previously reported encapsulation systems, BZ emulsions and BZ vesicles. Oscillation studies on individual LMs established PE-coated LMs were easier to prepare and more robust than PTFE-coated LMs. Therefore, this coating was used to study BZ LMs positioned in ordered and disordered arrays. Sporadic transfer of excitation waves was observed between LMs in close proximity to each other. These results lay the foundations for future studies on information transmission and processing arrays of BZ LMs. Future work aims to elucidate the effect of other physical stimuli on the dynamics of chemical excitation waves withinthese systems
Neuromorphic liquid marbles with aqueous carbon nanotube cores
Neuromorphic computing devices attempt to emulate features of biological nervous systems through mimicking the properties of synapses, towards implementing the emergent properties of their counterparts, such as learning. Inspired by recent advances in the utilisation of liquid marbles (microlitre quantities of fluid coated in hydrophobic powder) for the creation of unconventional computing devices, we describe the development of liquid marbles with neuromorphic properties through the use of copper coatings and l.0mgml-1 carbon nanotube-containing fluid cores. Experimentation was performed through sandwiching the marbles between two cup-style electrodes and stimulating them with repeated DC pulses at 3.0 V. Our results demonstrate that 'entrainmentâ of a carbon nanotube filled-copper liquid marble via periodic pulses can cause their electrical resistance to rapidly switch between high to low resistance profiles, upon inverting the polarity of stimulation: The reduction in resistance between high and low profiles was approximately 88% after two rounds of entrainment. This effect was found to be reversible through reversion to the original stimulus polarity and was strengthened by repeated experimentation, as evidenced by a mean reduction in time to switching onset of 43%. These effects were not replicated in nanotube solutions not bound inside liquid marbles. Our electrical characterisation also reveals that nanotube-filled liquid marbles exhibit pinched loop hysteresis IV profiles consistent with the description of memristors. We conclude by discussing the applications of this technology to the development of unconventional computing devices and the study of emergent characteristics in biological neural tissue
Mapping outcomes of liquid marble collisions
© 2019 The Royal Society of Chemistry. Liquid marbles (LMs) have many promising roles in the ongoing development of microfluidics, microreactors, bioreactors, and unconventional computing. In many of these applications, the coalescence of two LMs is either required or actively discouraged, therefore it is important to study liquid marble collisions and establish parameters which enable the desired collision outcome. Recent reports on LM coalescence have focused on either two mobile LMs colliding, or an accelerating LM hitting a sessile LM with a backstop. A further possible scenario is the impact of a mobile LM against a non-supported static LM. This paper investigates such a collision, using high-speed videography for single-frame analysis. Multiple collisions were undertaken whilst varying the modified Weber number (Weâ) and offset ratios (Xâ). Parameter ranges of 1.0 0.25, and Weâ 1.55 resulted in 100% non-coalescence. Additionally, observations of LMs moving above a threshold velocity of 0.6 m s -1 have revealed a new and unusual deformation. Comparisons of the outcome of collisions whilst varying both the LM volume and the powder grain size have also been made, revealing a strong link. The results of this work provide a deeper understanding of LM coalescence, allowing improved control when designing future collision experiments
Mechanical sequential counting with liquid marbles
© 2018, Springer International Publishing AG, part of Springer Nature. Here we demonstrate the first working example of a liquid marble-operated sequential binary counting device. We have designed a lightweight gate that can be actuated by the low mass and momentum of a liquid marble. By linking a number of these gates in series, we are able to digitally count up to binary 1111 (upper limit only by our requirements). Using liquid marbles in such a system opens up new avenues of research and design, by way of modifying the coating and/or core of the liquid marbles, and thereby giving extra dimensions for calculation (e.g. a calculation that takes into consideration the progress of a chemical reaction inside a liquid marble). In addition, the new gate design has multiple uses in liquid marble rerouting
Crisis resolution and home treatment in the UK: A survey of model fidelity using a novel review methodology
Crisis resolution teams (CRTs) provide treatment at home to people experiencing mental health crises, as an alternative to hospital admission. Previous UK research, based on selfâreport surveys, suggests that a loosely specified model has resulted in wide variations in CRTsâ service delivery, organization and outcomes. A fidelity scale (developed through evidence review and stakeholder consensus) provided a means of objectively measuring adherence to a model of good practice for CRTs, via oneâday fidelity reviews of UK crisis teams. Reviews included interviews with service users, carers, staff and managers, and examination of data, policies, protocols and anonymized case notes. Of the 75 teams reviewed, 49 (65%) were assessed as being moderate fidelity and the rest as low fidelity, with no team achieving high fidelity. The median score was 122 (range: 73â151; interâquartile range: 111â132). Teams achieved higher scores on items about structure and organization, for example ease of referral, medication and safety systems, but scored poorly on items about the content of care and interventions. Despite a national mandate to implement the CRT model, there are wide variations in implementation in the UK and no teams in our sample achieved overall high fidelity. This suggests that a mandatory national policy is not in itself sufficient to achieve good quality implementation of a service model. The CRT Fidelity Scale provides a feasible and acceptable means to objectively assess model fidelity in CRTs. There is a need for development and testing of interventions to enhance model fidelity and facilitate improvements to these services
Improvement over time in outcomes for patients undergoing endoscopic therapy for Barrett's oesophagus-related neoplasia: 6-year experience from the first 500 patients treated in the UK patient registry.
BACKGROUND: Barrett's oesophagus (BE) is a pre-malignant condition leading to oesophageal adenocarcinoma (OAC). Treatment of neoplasia at an early stage is desirable. Combined endoscopic mucosal resection (EMR) followed by radiofrequency ablation (RFA) is an alternative to surgery for patients with BE-related neoplasia. METHODS: We examined prospective data from the UK registry of patients undergoing RFA/EMR for BE-related neoplasia from 2008 to 2013. Before RFA, visible lesions were removed by EMR. Thereafter, patients had RFA 3-monthly until all BE was ablated or cancer developed (endpoints). End of treatment biopsies were recommended at around 12â
months from first RFA treatment or when endpoints were reached. Outcomes for clearance of dysplasia (CR-D) and BE (CR-IM) at end of treatment were assessed over two time periods (2008-2010 and 2011-2013). Durability of successful treatment and progression to OAC were also evaluated. RESULTS: 508 patients have completed treatment. CR-D and CR-IM improved significantly between the former and later time periods, from 77% and 56% to 92% and 83%, respectively (p<0.0001). EMR for visible lesions prior to RFA increased from 48% to 60% (p=0.013). Rescue EMR after RFA decreased from 13% to 2% (p<0.0001). Progression to OAC at 12â
months is not significantly different (3.6% vs 2.1%, p=0.51). CONCLUSIONS: Clinical outcomes for BE neoplasia have improved significantly over the past 6â
years with improved lesion recognition and aggressive resection of visible lesions before RFA. Despite advances in technique, the rate of cancer progression remains 2-4% at 1â
year in these high-risk patients. TRIAL REGISTRATION NUMBER: ISRCTN93069556
Liquid Marble Actuator for Microfluidic Logic Systems
© 2018, The Author(s). A mechanical flip-flop actuator has been developed that allows for the facile re-routing and distribution of liquid marbles (LMs) in digital microfluidic devices. Shaped loosely like a triangle, the actuating switch pivots from one bistable position to another, being actuated by the very low mass and momentum of a LM rolling under gravity (~4 Ă 10 â6 kg ms â1 ). The actuator was laser-cut from cast acrylic, held on a PTFE coated pivot, and used a PTFE washer. Due to the rocking motion of the switch, sequential LMs are distributed along different channels, allowing for sequential LMs to traverse parallel paths. This distributing effect can be easily cascaded, for example to evenly divide sequential LMs down four different paths. This lightweight, cheap and versatile actuator has been demonstrated in the design and construction of a LM-operated mechanical multiplication device â establishing its effectiveness. The actuator can be operated solely by gravity, giving it potential use in point-of-care devices in low resource areas
Crisis resolution teams for people experiencing mental health crises: the CORE mixed-methods research programme including two RCTs
Background Crisis resolution teams (CRTs) seek to avert hospital admissions by providing intensive home treatment for people experiencing a mental health crisis. The CRT model has not been highly specified. CRT care is often experienced as ending abruptly and relapse rates following CRT discharge are high. Aims The aims of CORE (Crisis resolution team Optimisation and RElapse prevention) workstream 1 were to specify a model of best practice for CRTs, develop a measure to assess adherence to this model and evaluate service improvement resources to help CRTs implement the model with high fidelity. The aim of CORE workstream 2 was to evaluate a peer-provided self-management programme aimed at reducing relapse following CRT support. Methods Workstream 1 was based on a systematic review, national CRT manager survey and stakeholder qualitative interviews to develop a CRT fidelity scale through a concept mapping process with stakeholders (n = 68). This was piloted in CRTs nationwide (n = 75). A CRT service improvement programme (SIP) was then developed and evaluated in a cluster randomised trial: 15 CRTs received the SIP over 1 year; 10 teams acted as controls. The primary outcome was service user satisfaction. Secondary outcomes included CRT model fidelity, catchment area inpatient admission rates and staff well-being. Workstream 2 was a peer-provided self-management programme that was developed through an iterative process of systematic literature reviewing, stakeholder consultation and preliminary testing. This intervention was evaluated in a randomised controlled trial: 221 participants recruited from CRTs received the intervention and 220 did not. The primary outcome was re-admission to acute care at 1 year of follow-up. Secondary outcomes included time to re-admission and number of days in acute care over 1 year of follow-up and symptoms and personal recovery measured at 4 and 18 monthsâ follow-up. Results Workstream 1 â a 39-item CRT fidelity scale demonstrated acceptability, face validity and promising inter-rater reliability. CRT implementation in England was highly variable. The SIP trial did not produce a positive result for patient satisfaction [median Client Satisfaction Questionnaire score of 28 in both groups at follow-up; coefficient 0.97, 95% confidence interval (CI) â1.02 to 2.97]. The programme achieved modest increases in model fidelity. Intervention teams achieved lower inpatient admission rates and less inpatient bed use. Qualitative evaluation suggested that the programme was generally well received. Workstream 2 â the trial yielded a statistically significant result for the primary outcome, in which rates of re-admission to acute care over 1 year of follow-up were lower in the intervention group than in the control group (odds ratio 0.66, 95% CI 0.43 to 0.99; p = 0.044). Time to re-admission was lower and satisfaction with care was greater in the intervention group at 4 monthsâ follow-up. There were no other significant differences between groups in the secondary outcomes. Limitations Limitations in workstream 1 included uncertainty regarding the representativeness of the sample for the primary outcome and lack of blinding for assessment. In workstream 2, the limitations included the complexity of the intervention, preventing clarity about which were effective elements. Conclusions The CRT SIP did not achieve all its aims but showed potential promise as a means to increase CRT model fidelity and reduce inpatient service use. The peer-provided self-management intervention is an effective means to reduce relapse rates for people leaving CRT care. Study registration The randomised controlled trials were registered as Current Controlled Trials ISRCTN47185233 and ISRCTN01027104. The systematic reviews were registered as PROSPERO CRD42013006415 and CRD42017043048. Funding The National Institute for Health Research Programme Grants for Applied Research programme
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