Properties of Si quantum dots

The fundamental properties of matter in confined particles change dramatically due to quantum effects. In this work, we have explored the optical properties of silicon quantum dots (Si-QDs) embedded in Si3N4; and the role of crystallinity on the optical properties and formation of Si-QDs in Al2O3. This work examined the role of (1) annealing temperature and the composition of the film, (2) Al doping of the host Si3N4 film, (3) doping Si-QDs and (4) Al and P passivation of Si-QDs on the PL intensity of Si-QDs embedded in Si3N4. Photoluminescence (PL), time-resolved photoluminescence (TRPL), X-ray absorption near edge spectroscopy (XANES), X-ray excited optical luminescence (XEOL), elastic recoil detection (ERD), positron annihilation spectroscopy (PAS) and Fourier-Transform infrared (FTIR) spectroscopy measurements were used for characterization. We have found that the luminescence originated from both quantum confinement effects and defects. H, Al and P passivation was found to increase the PL intensity of Si-QDs in Si3N4 while impurities such as Cr3+ and oxygen vacancies dominate the PL spectra for Si-QDs in Al2O3

A pilot study of the S-MAP (Solutions for Medications Adherence Problems) intervention for older adults prescribed polypharmacy in primary care: Study protocol

Background: Adhering to multiple medications as prescribed is challenging for older patients (aged ≥ 65 years) and a difficult behaviour to improve. Previous interventions designed to address this have been largely complex in nature but have shown limited effectiveness and have rarely used theory in their design. It has been recognised that theory ('a systematic way of understanding events or situations') can guide intervention development and help researchers better understand how complex adherence interventions work. This pilot study aims to test a novel community pharmacy-based intervention that has been systematically developed using the Theoretical Domains Framework (12-domain version) of behaviour change. Methods: As part of a non-randomised pilot study, pharmacists in 12 community pharmacies across Northern Ireland (n = 6) and London, England (n = 6), will be trained to deliver the intervention to older patients who are prescribed ≥ 4 regular medicines and are non-adherent (self-reported). Ten patients will be recruited per pharmacy (n = 120) and offered up to four tailored one-to-one sessions, in the pharmacy or via telephone depending on their adherence, over a 3-4-month period. Guided by an electronic application (app) on iPads, the intervention content will be tailored to each patient's underlying reasons for non-adherence and mapped to the most appropriate solutions using established behaviour change techniques. This study will assess the feasibility of collecting data on the primary outcome of medication adherence (self-report and dispensing data) and secondary outcomes (health-related quality of life and unplanned hospitalisations). An embedded process evaluation will assess training fidelity for pharmacy staff, intervention fidelity, acceptability to patients and pharmacists and the intervention's mechanism of action. Process evaluation data will include audio-recordings of training workshops, intervention sessions, feedback interviews and patient surveys. Analysis will be largely descriptive. Discussion: Using pre-defined progression criteria, the findings from this pilot study will guide the decision whether to proceed to a cluster randomised controlled trial to test the effectiveness of the S-MAP intervention in comparison to usual care in community pharmacies. The study will also explore how the intervention components may work to bring about change in older patients' adherence behaviour and guide further refinement of the intervention and study procedures. Trial registration: This study is registered at ISRCTN: https://doi.org/10.1186/ISRCTN7383153

57-Fe Mossbauer study of magnetic ordering in superconducting K_0.85Fe_1.83Se_2.09 single crystals

The magnetic ordering of superconducting single crystals of K_0.85Fe_1.83Se_2.09 has been studied between 10K and 550K using 57-Fe Mossbauer spectroscopy. Despite being superconducting below T_sc ~30K, the iron sublattice in K_0.85Fe_1.83Se_2.09 clearly exhibits magnetic order from well below T_sc to its N\'eel temperature of T_N = 532 +/- 2K. The iron moments are ordered perpendicular to the single crystal plates, i.e. parallel to the crystal c-axis. The order collapses rapidly above 500K and the accompanying growth of a paramagnetic component suggests that the magnetic transition may be first order, which may explain the unusual temperature dependence reported in recent neutron diffraction studies.Comment: 6 pages, 4 figures Submitted to Phys.Rev.

Measurement and modelling of mass diffusion coefficients for application in carbon dioxide storage and enhanced oil recovery

In this work, measurements were carried out by the Taylor dispersion method [1, 2] to determine the mutual diffusion coefficient for CO2 in water or hydrocarbon at effectively infinite dilution. Measurements were carried out for CO2 in water, hexane, heptane, octane, decane, dodecane, hexadecane, cyclohexane, squalane and toluene at temperatures between 298 K and 423 K with pressures up to 69 MPa. Measurements of CO2 diffusivity in different brines were also carried out by 13C pulsed-field gradient NMR

Surface charge reversal method for high-resolution inkjet printing of functional water-based inks

© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Printed electronics is a rapidly growing area of research being explored for the manufacture of large-area and cost-effective electronic devices by the patterned application of functional inks. There are challenges associated with processing the inks compatible with inkjet printing technology and developing effi cient methods to successfully obtain the desired features, particularly when it comes to metal and metal-organic complex inks. Here, a reliable method is developed to achieve a sophisticated microstructured pattern using the inkjet printing technique assisted by a surface charge reversal effect. In addition, a procedure is formulated to obtain good quality, stable metal-organic water-based inks compatible with salts of a variety of transition metals and rare earths, without the need for additional volatile solvents. A feasible and water-based ink formulation combined with a simple and noninvasive surface charge reversal treatment constitutes a major step toward the manufacture of high-resolution, inorganic patterned thin fi lms on hydrophobic substrates using inkjet printing. These outcomes lead to the path of effective fusion of inorganic and organic heterointerfaces by simples designing and printing.This work was supported by the University of New South Wales and Spanish MICINN (Consolider CSD2007-0041). A portion of this work was performed at the ACT node of the Australian National Fabrication Facility. The authors wish to acknowledge Dr. F. Kremer for the electron diffraction measurement.Peer Reviewe

Retrospective longitudinal study of patients and prescriber characteristics associated with new DOAC prescriptions in a CCG without restrictions to DOAC use

yesDirect oral anticoagulants (DOACs) uptake for stroke prevention in atrial fibrillation has been slow.[1] This study aimed to profile the prescribing of DOACs over three years to identify factors associated with DOAC prescribing in a Clinical Commissioning Group (CCG) without restrictions to DOACs use. The objectives were to identify: - Characteristics of patients prescribed oral anticoagulant (OAC) in a sample of general practices; - Who initiated the prescribing of OAC; - Recorded reasons for prescribing a DOAC rather than warfarin

Improving adherence to multiple medications in older people in primary care: Selecting intervention components to address patient-reported barriers and facilitators

Background: Medication adherence is vital to ensuring optimal patient outcomes, particularly amongst multimorbid older people prescribed multiple medications. Interventions targeting adherence often lack a theoretical underpinning and this may impact on effectiveness. The theoretical domains framework (TDF) of behaviour can aid intervention development by systematically identifying key determinants of medication adherence. Objectives: This study aimed to (i) identify determinants (barriers, facilitators) of adherence to multiple medications from older people's perspectives; (ii) identify key domains to target for behaviour change; and (iii) map key domains to intervention components [behaviour change techniques (BCTs)] that could be delivered in an intervention by community pharmacists. Method Focus groups were conducted with older people (>65 years) receiving ≥4 medications. Questions explored the 12 domains of the TDF (eg “Knowledge,” “Emotion”). Data were analysed using the framework method and content analysis. Identification of key domains and mapping to intervention components (BCTs) followed established methods. Results: Seven focus groups were convened (50 participants). A wide range of determinants were identified as barriers (eg forgetfulness, prioritization of medications) and facilitators (eg social support, personalized routines) of adherence to multiple medications. Eight domains were identified as key targets for behaviour change (eg “Social influences,” “Memory, attention and decision processes,” “Motivation and goals”) and mapped to 11 intervention components (BCTs) to include in an intervention [eg “Social support or encouragement (general),” “Self-monitoring of the behaviour,” “Goal-setting (behaviour)”]. Conclusion: This study used a theoretical underpinning to identify potential intervention components (BCTs). Future work will incorporate the selected BCTs into an intervention that will undergo feasibility testing in community pharmacies

A feasibility study of a theory-based intervention to improve appropriate polypharmacy for older people in primary care

Background: A general practitioner (GP)-targeted intervention aimed at improving the prescribing of appropriate polypharmacy for older people was previously developed using a systematic, theory-based approach based on the UK Medical Research Council’s complex intervention framework. The primary intervention component comprised a video demonstration of a GP prescribing appropriate polypharmacy during a consultation with an older patient. The video was delivered to GPs online and included feedback emphasising the positive outcomes of performing the behaviour. As a complementary intervention component, patients were invited to scheduled medication review consultations with GPs. This study aimed to test the feasibility of the intervention and study procedures (recruitment, data collection). Methods: GPs from two general practices were given access to the video, and reception staff scheduled consultations with older patients receiving polypharmacy (≥4 medicines). Primary feasibility study outcomes were the usability and acceptability of the intervention to GPs. Feedback was collected from GP and patient participants using structured questionnaires. Clinical data were also extracted from recruited patients’ medical records (baseline and 1 month post-consultation). The feasibility of applying validated assessment of prescribing appropriateness (STOPP/ START criteria, Medication Appropriateness Index) and medication regimen complexity (Medication Regimen Complexity Index) to these data was investigated. Data analysis was descriptive, providing an overview of participants’ feedback and clinical assessment findings. Results: Four GPs and ten patients were recruited across two practices. The intervention was considered usable and acceptable by GPs. Some reservations were expressed by GPs as to whether the video truly reflected resource and time pressures encountered in the general practice working environment. Patient feedback on the scheduled consultations was positive. Patients welcomed the opportunity to have their medications reviewed. Due to the short time to follow-up and a lack of detailed clinical information in patient records, it was not feasible to detect any prescribing changes or to apply the assessment tools to patients’ clinical data. Conclusion: The findings will help to further refine the intervention and study procedures (including time to follow-up) which will be tested in a randomised pilot study that will inform the design of a definitive trial to evaluate the intervention’s effectiveness