Ligand-Directed Self-Assembly of Organic-Semiconductor/Quantum-Dot Blend Films Enables Efficient Triplet Exciton-Photon Conversion.

Blends comprising organic semiconductors and inorganic quantum dots (QDs) are relevant for many optoelectronic applications and devices. However, the individual components in organic-QD blends have a strong tendency to aggregate and phase-separate during film processing, compromising both their structural and electronic properties. Here, we demonstrate a QD surface engineering approach using electronically active, highly soluble semiconductor ligands that are matched to the organic semiconductor host material to achieve well-dispersed inorganic-organic blend films, as characterized by X-ray and neutron scattering, and electron microscopies. This approach preserves the electronic properties of the organic and QD phases and also creates an optimized interface between them. We exemplify this in two emerging applications, singlet-fission-based photon multiplication (SF-PM) and triplet-triplet annihilation-based photon upconversion (TTA-UC). Steady-state and time-resolved optical spectroscopy shows that triplet excitons can be transferred with near unity efficiently across the organic-inorganic interface, while the organic films maintain efficient SF (190% yield) in the organic phase. By changing the relative energy between organic and inorganic components, yellow upconverted emission is observed upon 790 nm NIR excitation. Overall, we provide a highly versatile approach to overcome longstanding challenges in the blending of organic semiconductors with QDs that have relevance for many optical and optoelectronic applications.

Delivering motivational interviewing early post stroke: standardisation of the intervention.

BACKGROUND: We applied Motivational Interviewing (MI) techniques, early after stroke, to facilitate psychological adjustment to life post-stroke. In our trial, MI-plus-usual-care increased the likelihood of normal mood at 3-months post-stroke, compared to usual-care alone. Whilst appropriate training, manuals, and supervision may increase adherence to core principles of this complex intervention, unintended variability in implementation inevitably remains. We aimed to explore the impact of variability on participant outcome. METHODS: Using our trial data (411 participants), we explored variation in MI delivery, examining: therapist characteristics (stroke care expertise/knowledge, psychology training); MI content (fidelity to MI techniques assessed with Motivational Interviewing Treatment Integrity code, describing therapist behaviours as MI-consistent, MI-neutral or MI-inconsistent); and MI dose (number/duration of sessions). RESULTS: The four MI therapists (two nurses/two psychologists) had varying expertise and MI delivery. Across therapists, mean average session duration ranged 29.5-47.8 min. The percentage of participants completing the per-protocol four sessions ranged 47%-74%. These variations were not related to participant outcome. There were uniformly high frequencies (>99%) of MI-consistent and MI-neutral interactions, and low frequencies (<1%) of MI-inconsistent interactions. CONCLUSIONS: Variation in therapist characteristics and MI dose did not affect participant outcome. These may have been tolerated due to high fidelity to MI principles.IMPLICATIONS FOR REHABILITATIONMotivational Interviewing (MI) can help reduce depression in stroke survivors when delivered early after stroke.The effectiveness of our MI intervention depends on the delivery of high quality MI; in particular, interactions with low levels of MI-inconsistency, and high global MI ratings, ideally delivered over more than one session, each lasting at least 30 minutes.Provided high quality MI is being delivered, the intervention can still have a beneficial effect on participant outcome, even with flexibility and variation in therapist characteristics, and duration and number of sessions, which may be inevitable in a clinical context.

Stroke in India: A systematic review of the incidence, prevalence, and case fatality.

BACKGROUND: The burden of stroke is increasing in India; stroke is now the fourth leading cause of death and the fifth leading cause of disability. Previous research suggests that the incidence of stroke in India ranges between 105 and 152/100,000 people per year. However, there is a paucity of available data and a lack of uniform methods across published studies. AIM: To identify high-quality prospective studies reporting the epidemiology of stroke in India. SUMMARY OF REVIEW: A search strategy was modified from the Cochrane Stroke Strategy and adapted for a range of bibliographic databases from January 1997 to August 2020. From 7717 identified records, nine studies were selected for inclusion; three population-based registries, a further three population-based registries also using community-based ascertainment and three community-based door-to-door surveys. Studies represented the four cities of Mumbai, Trivandrum, Ludhiana, Kolkata, the state of Punjab, and 12 villages of Baruipur in the state of West Bengal. The total population denominator was 22,479,509 and 11,654 (mean 1294 SD 1710) people were identified with incident stroke. Crude incidence of stroke ranged from 108 to 172/100,000 people per year, crude prevalence from 26 to 757/100,000 people per year, and one-month case fatality rates from 18% to 42%. CONCLUSIONS: Further high-quality evidence is needed across India to guide stroke policy and inform the development and organization of stroke services. Future researchers should consider the World Health Organization STEPwise approach to Surveillance framework, including longitudinal data collection, the inclusion of census population data, and a combination of hospital-registry and comprehensive community ascertainment strategies to ensure complete stroke identification.

Photocurrent in Metal-Halide Perovskite/Organic Semiconductor Heterostructures: Impact of Microstructure on Charge Generation Efficiency.

Hybrid organic-inorganic metal-halide perovskites have emerged as versatile materials for enabling low-cost, mechanically flexible optoelectronic applications. The progress has been commendable; however, technological breakthroughs have outgrown the basic understanding of processes occurring in bulk and at device interfaces. Here, we investigated the photocurrent at perovskite/organic semiconductor interfaces in relation to the microstructure of electronically active layers. We found that the photocurrent response is significantly enhanced in the bilayer structure as a result of a more efficient dissociation of the photogenerated excitons and trions in the perovskite layer. The increase in the grain size within the organic semiconductor layer results in reduced trapping and further enhances the photocurrent by extending the photocarriers' lifetime. The photodetector responsivity and detectivity have improved by 1 order of magnitude in the optimized samples, reaching values of 6.1 ± 1.1 A W-1, and 1.5 × 1011 ± 4.7 × 1010 Jones, respectively, and the current-voltage hysteresis has been eliminated. Our results highlight the importance of fine-tuning film microstructure in reducing the loss processes in thin-film optoelectronics based on metal-halide semiconductors and provide a powerful interfacial design method to consistently achieve high-performance photodetectors.

Emissive spin-0 triplet-pairs are a direct product of triplet-triplet annihilation in pentacene single crystals and anthradithiophene films.

Singlet fission and triplet-triplet annihilation represent two highly promising ways of increasing the efficiency of photovoltaic devices. Both processes are believed to be mediated by a biexcitonic triplet-pair state, 1(TT). Recently however, there has been debate over the role of 1(TT) in triplet-triplet annihilation. Here we use intensity-dependent, low-temperature photoluminescence measurements, combined with kinetic modelling, to show that distinct 1(TT) emission arises directly from triplet-triplet annihilation in high-quality pentacene single crystals and anthradithiophene (diF-TES-ADT) thin films. This work demonstrates that a real, emissive triplet-pair state acts as an intermediate in both singlet fission and triplet-triplet annihilation and that this is true for both endo- and exothermic singlet fission materials.

Organic Field-Effect Transistors as Flexible, Tissue-Equivalent Radiation Dosimeters in Medical Applications.

Radiation therapy is one of the most prevalent procedures for cancer treatment, but the risks of malignancies induced by peripheral beam in healthy tissues surrounding the target is high. Therefore, being able to accurately measure the exposure dose is a critical aspect of patient care. Here a radiation detector based on an organic field-effect transistor (RAD-OFET) is introduced, an in vivo dosimeter that can be placed directly on a patient's skin to validate in real time the dose being delivered and ensure that for nearby regions an acceptable level of low dose is being received. This device reduces the errors faced by current technologies in approximating the dose profile in a patient's body, is sensitive for doses relevant to radiation treatment procedures, and robust when incorporated into conformal large-area electronics. A model is proposed to describe the operation of RAD-OFETs, based on the interplay between charge photogeneration and trapping.

Motivational interviewing for low mood and adjustment early after stroke: a feasibility randomised trial.

BACKGROUND: Management of psychological adjustment and low mood after stroke can result in positive health outcomes. We have adapted a talk-based therapy, motivational interviewing (MI), and shown it to be potentially effective for managing low mood and supporting psychological adjustment post-stroke in a single-centre trial. In the current study, we aimed to explore the feasibility of delivering MI using clinical stroke team members, and using an attention control (AC), to inform the protocol for a future definitive trial. METHODS: This parallel two-arm feasibility trial took place in north-west England. Recruitment occurred between December 2012 and November 2013. Participants were stroke patients aged 18 years or over, who were medically stable, had no severe communication problems, and were residents of the hospital catchment. Randomisation was to MI or AC, and was conducted by a researcher not involved in recruitment using opaque sealed envelopes. The main outcome measures were descriptions of study feasibility (recruitment/retention rates, MI delivery by clinical staff, use of AC) and acceptability (through qualitative interviews and completion of study measures), and fidelity to MI and AC (through review of session audio-recordings). Information was also collected on participants' mood, quality of life, adjustment, and resource-use. RESULTS: Over 12 months, 461 patients were screened, 124 were screened eligible, and 49 were randomised: 23 to MI, 26 to AC. At 3 months, 13 MI and 18 AC participants completed the follow-up assessment (63% retention). This was less than expected based on our original trial. An AC was successfully implemented. Alternative approaches would be required to ensure the feasibility of clinical staff delivering MI. The study measures, MI, and AC interventions were considered acceptable, and there was good fidelity to the interventions. There were no adverse events related to study participation. CONCLUSIONS: It was possible to recruit and retain participants, train clinical staff to deliver MI, and implement an appropriate AC. Changes would be necessary to conduct a future multi-centre trial, including: assuming a recruitment rate lower than that in the current study; implementing more strategies to increase participant retention; and considering alternative clinical staff groups to undertake the delivery of MI and AC. TRIAL REGISTRATION: ISRCTN study ID: ISRCTN55624892. TRIAL FUNDING: Northern Stroke Research Fund.

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.

The validity and acceptability of a text-based monitoring system for pediatric asthma studies.

A meaningful analysis in research requires robust, valid data. Paper diaries allow the collection of data from individuals over time but are notorious for poor compliance and validity. SMS-technology is a novel method for data collection in medical research. Time-tagged SMS are transferred directly to an electronic file. We used SMS to collect symptoms and peak flow rate (PEFR) meter readings from 32 children with asthma. Parents responded first to five SMS daily for 7 days during an asymptomatic period and then for 14 days during a cold. Compliance with use of PEFR meter and SMS system were assessed. Digital PEFR meters enabled data download at the end of the study to confirm validity of transmitted data. Parents of 24 participants provided feedback about this data collection tool. Mean (±SD) "SMS-diary and PEFR-meter compliance" were 96% (±8) and 84% (±21) during baseline and 91% (±12) and 82% (±20) during cold respectively. Correctly reported PEFR values were found in 65.5% of all cases, in 8.3% PEFR values sent were "self-invented" and 2.4% of values were missing. All of the 22 parents completing the baseline questionnaire were happy to use SMS for this study. Of the 20 parents completing the follow up questionnaire, 95% (19/20) found the system user-friendly, 55% (11/20) would be more likely to participate in studies if they were using SMS data collection and 25% (5/20) were "sometimes unhappy" about receiving messages. This real-time capture of data is well accepted and could avoid some of the pitfalls of backfilled paper diaries.

Activities to support the implementation of complex interventions as part of routine care: a review of the quality of reporting in cluster randomised controlled trials.

OBJECTIVE: To review a sample of cluster randomised controlled trials and explore the quality of reporting of (1) enabling or support activities provided to the staff during the trial, (2) strategies used to monitor fidelity throughout the trial and (3) the extent to which the intervention being tested was delivered as planned. DESIGN: A descriptive review. DATA SOURCES AND STUDY SELECTION: We searched MEDLINE for trial reports published between 2008 and 2014 with combinations of the search terms 'randomised', 'cluster', 'trial', 'study', 'intervention' and 'implement*'. We included trials in which healthcare professionals (HCPs) implemented the intervention being tested as part of routine practice. We excluded trials (1) conducted in non-health services settings, (2) where the intervention explicitly aimed to change the behaviours of the HCPs and (3) where the trials were ongoing or for which only trial protocols were available. DATA COLLECTION: We developed a data extraction form using the Template for Intervention Description and Replication (TIDieR checklist). Review authors independently extracted data from the included trials and assessed quality of reporting for individual items. RESULTS: We included 70 publications (45 results publications, 25 related publications). 89% of trials reported using enabling or support activities. How these activities were provided (75.6%, n=34) and how much was provided (73.3%, n=33) were the most frequently reported items. Less than 20% (n=8) of the included trials reported that competency checking occurred prior to implementation and data collection. 64% (n=29) of trials reported collecting measures of implementation. 44% (n=20) of trials reported data from these measures. CONCLUSIONS: Although enabling and support activities are reported in trials, important gaps exist when assessed using an established checklist. Better reporting of the supports provided in effectiveness trials will allow for informed decisions to be made about financial and resource implications for wide scale implementation of effective interventions.

Australian Diabetes Foot Network: practical guideline on the provision of footwear for people with diabetes.

Trauma, in the form of pressure and/or friction from footwear, is a common cause of foot ulceration in people with diabetes. These practical recommendations regarding the provision of footwear for people with diabetes were agreed upon following review of existing position statements and clinical guidelines. The aim of this process was not to re-invent existing guidelines but to provide practical guidance for health professionals on how they can best deliver these recommendations within the Australian health system. Where information was lacking or inconsistent, a consensus was reached following discussion by all authors. Appropriately prescribed footwear, used alone or in conjunction with custom-made foot orthoses, can reduce pedal pressures and reduce the risk of foot ulceration. It is important for all health professionals involved in the care of people with diabetes to both assess and make recommendations on the footwear needs of their clients or to refer to health professionals with such skills and knowledge. Individuals with more complex footwear needs (for example those who require custom-made medical grade footwear and orthoses) should be referred to health professionals with experience in the prescription of these modalities and who are able to provide appropriate and timely follow-up. Where financial disadvantage is a barrier to individuals acquiring appropriate footwear, health care professionals should be aware of state and territory based equipment funding schemes that can provide financial assistance. Aboriginal and Torres Strait Islanders and people living in rural and remote areas are likely to have limited access to a broad range of footwear. Provision of appropriate footwear to people with diabetes in these communities needs be addressed as part of a comprehensive national strategy to reduce the burden of diabetes and its complications on the health system.

Australian Diabetes Foot Network: management of diabetes-related foot ulceration - a clinical update.

Appropriate assessment and management of diabetes-related foot ulcers (DRFUs) is essential to reduce amputation risk. Management requires debridement, wound dressing, pressure off-loading, good glycaemic control and potentially antibiotic therapy and vascular intervention. As a minimum, all DRFUs should be managed by a doctor and a podiatrist and/or wound care nurse. Health professionals unable to provide appropriate care for people with DRFUs should promptly refer individuals to professionals with the requisite knowledge and skills. Indicators for immediate referral to an emergency department or multidisciplinary foot care team (MFCT) include gangrene, limb-threatening ischaemia, deep ulcers (bone, joint or tendon in the wound base), ascending cellulitis, systemic symptoms of infection and abscesses. Referral to an MFCT should occur if there is lack of wound progress after 4 weeks of appropriate treatment.