442 research outputs found

    Optimization of a high work function solution processed vanadium oxide hole-extracting layer for small molecule and polymer organic photovoltaic cells

    Get PDF
    We report a method of fabricating a high work function, solution processable vanadium oxide (V2Ox(sol)) hole-extracting layer. The atmospheric processing conditions of film preparation have a critical influence on the electronic structure and stoichiometry of the V2Ox(sol), with a direct impact on organic photovoltaic (OPV) cell performance. Combined Kelvin probe (KP) and ultraviolet photoemission spectroscopy (UPS) measurements reveal a high work function, n-type character for the thin films, analogous to previously reported thermally evaporated transition metal oxides. Additional states within the band gap of V2Ox(sol) are observed in the UPS spectra and are demonstrated using X-ray photoelectron spectroscopy (XPS) to be due to the substoichiometric nature of V2Ox(sol). The optimized V2Ox(sol) layer performance is compared directly to bare indiumā€“tin oxide (ITO), poly(ethyleneoxythiophene):poly(styrenesulfonate) (PEDOT:PSS), and thermally evaporated molybdenum oxide (MoOx) interfaces in both small molecule/fullerene and polymer/fullerene structures. OPV cells incorporating V2Ox(sol) are reported to achieve favorable initial cell performance and cell stability attributes

    Measuring physical activity levels in people with mild cognitive impairment or mild dementia

    Get PDF
    Measuring physical activity (PA) in people with mild cognitive impairment (MCI) or dementia can be difficult. The aim was to investigate the validity and acceptability of three different PA measurement methods.The mixed-method analysis included 49 participants with MCI or dementia who completed a daily calendar recording PA, the International Physical Activity Questionnaire (IPAQ), the LASA Physical Activity Questionnaire and wore a Misfit Shine accelerometer. The quantitative analysis showed equal completion rates for the IPAQ questionnaire and the accelerometer but a lower completion rate for the calendar. Correlations between outcome measures were moderate or strong. The qualitative analysis indicated that all measures were acceptable, though help to complete the calendars or fasten the accelerometers was required for some participants. The study supported the validity of these methods for people with MCI and mild dementia. Using accelerometers and completing calendars might increase motivation to be active for some people

    Buffer gas cooling and trapping of atoms with small magnetic moments

    Full text link
    Buffer gas cooling was extended to trap atoms with small magnetic moment (mu). For mu greater than or equal to 3mu_B, 1e12 atoms were buffer gas cooled, trapped, and thermally isolated in ultra high vacuum with roughly unit efficiency. For mu < 3mu_B, the fraction of atoms remaining after full thermal isolation was limited by two processes: wind from the rapid removal of the buffer gas and desorbing helium films. In our current apparatus we trap atoms with mu greater than or equal to 1.1mu_B, and thermally isolate atoms with mu greater than or equal to 2mu_B. Extrapolation of our results combined with simulations of the loss processes indicate that it is possible to trap and evaporatively cool mu = 1mu_B atoms using buffer gas cooling.Comment: 17 pages, 4 figure

    Interactions between amiodarone and the hERG potassium channel pore determined with mutagenesis and in silico docking

    Get PDF
    AbstractThe antiarrhythmic drug amiodarone delays cardiac repolarisation through inhibition of hERG-encoded potassium channels responsible for the rapid delayed rectifier potassium current (IKr). This study aimed to elucidate molecular determinants of amiodarone binding to the hERG channel. Whole-cell patch-clamp recordings were made at 37Ā°C of ionic current (IhERG) carried by wild-type (WT) or mutant hERG channels expressed in HEK293 cells. Alanine mutagenesis and ligand docking were used to investigate the roles of pore cavity amino-acid residues in amiodarone binding. Amiodarone inhibited WT outward IhERG tails with a half-maximal inhibitory concentration (IC50) of āˆ¼45nM, whilst inward IhERG tails in a high K+ external solution ([K+]e) of 94mM were blocked with an IC50 of 117.8nM. Amiodaroneā€™s inhibitory action was contingent upon channel gating. Alanine-mutagenesis identified multiple residues directly or indirectly involved in amiodarone binding. The IC50 for the S6 aromatic Y652A mutation was increased to āˆ¼20-fold that of WT IhERG, similar to the pore helical mutant S624A (āˆ¼22-fold WT control). The IC50 for F656A mutant IhERG was āˆ¼17-fold its corresponding WT control. Computational docking using a MthK-based hERG model differentiated residues likely to interact directly with drug and those whose Ala mutation may affect drug block allosterically. The requirements for amiodarone block of aromatic residues F656 and Y652 within the hERG pore cavity are smaller than for other high affinity IhERG inhibitors, with relative importance to amiodarone binding of the residues investigated being S624Aāˆ¼Y652A>F656A>V659A>G648A>T623A

    Preferential closed channel blockade of HERG potassium currents by chemically synthesised BeKmā€1 scorpion toxin

    Get PDF
    The scorpion toxin peptide BeKmā€1 was synthesised by fluorenylmethoxycarbonyl solid phase chemistry and folded by air oxidation. The peptide's effects on heterologous human etherā€aā€goā€goā€related gene potassium current (I HERG) in HEK293 cells were assessed using 'wholeā€cell' patch clamp. Blockade of I HERG by BeKmā€1 was concentrationā€dependent, temperatureā€dependent, and rapid in onset and reversibility. Blockade also exhibited inverse voltage dependence, inverse dependence on duration of depolarisation, and reverse useā€ and frequencyā€dependence. Blockade by BeKmā€1 and recombinant ergtoxin, another scorpion toxin known to block HERG, differed in their recovery from HERG current inactivation elicited by strong depolarisation and in their ability to block HERG when the channels were already activated. We conclude that synthetic BeKmā€1 toxin blocks HERG preferentially through a closed (resting) state channel blockade mechanism, although some open channel blockade also occurs

    A group singing program improves quality of life: An international study

    Get PDF
    People with Parkinsonā€™s (PwPs) may experience stigma, isolation, stress and anxiety due to the chronic nature of Parkinsonā€™s. Complementary therapies, including singing, have been reported to impact positively on quality of life (QoL) in PwPs. This paper reports on an international trial of Sing to Beat Parkinsonā€™sĀ®, a community group singing program, involving PwPs from Australia, the UK, and South Korea on QoL and mental well-being. PwPs (N=95; mean age=70.26; male 45%) participated in a standardized 6-month weekly group singing program, which included breathing exercises, vocal warm-ups and preferred song singing. PDQ39 and modified DASS21 were administered at baseline and follow-up to assess QoL and mental well-being, respectively. MANOVA and ANOVAs were performed with significance set as p<.05. MANOVA showed statistically significant multivariate effects of Time, Country, Time by Country and Time by Gender interactions on QoL. Follow-up univariate ANOVAs revealed main effects of Time on Stigma and Social Support domains of QoL; both improved. Further, MANOVA revealed a multivariate effect of Time on mental well-being; anxiety and stress significantly decreased from pre-test to post-test. This first international singing study with PwPs demonstrated that group singing enhanced some aspects of quality of life and mental well-being. Participating in a weekly group singing program for a 6-month period impacted positively on social support, and feeling stigmatized, as well as reductions in anxiety and stress. The findings are encouraging and warrant further research using more robust designs that include comparator groups.I was one of the travel grants recipients and the Health and Social Care Research Centre has supported me to attend this conference. The poster abstract will be published in Journal of Parkinson's Disease

    Development of a motivation communication training programme to aid diabetes-specialist podiatrists with adherence discussions

    Get PDF
    Diabetic foot ulcers (DFUs) impact a substantial proportion of patients with diabetes, with high recurrence rates, severe complications, and significant financial burden to health care systems. Adherence to treatment advice (e.g., limiting weight-bearing activity) is low with patients reporting dissatisfaction with the way in which advice is communicated. This study aimed to address this problem via the systematic development of a motivation communication training program. The program was designed to support diabetes-specialist podiatrists in empowering patients to actively engage with treatment. The development process followed an intervention mapping approach. Needs assessment involved observations of 24 patientā€“practitioner consultations within a diabetes-specialist foot clinic. This informed specification of a theory of change (self-determination theory) and relevant evidence-based communication strategies (drawing from motivational interviewing). The training program was developed iteratively with changes made following feedback from five diabetic foot health care professionals. The resulting training program, consisting of six one-hour face-to-face sessions over an 8-week period, was delivered to a further six diabetes specialist podiatrists, with five participating in postprogram telephone interviews to assess acceptability. Deductive thematic analysis of interview data revealed positive aspects of the training (e.g., valuable and relevant content), ideas for improvement (e.g., online resources and context-specific video examples), the acceptability of motivation strategies, and challenges putting the strategies into practice (such as time constraints and breaking old communication habits). This study contributes to our understanding of integrating motivation principles into routine consultations and holds potential for enhancing adherence to treatment recommendations in patients living with diabetic foot ulcers

    Motivation communication training programme for healthcare professionals to support adherence in patients with diabetic foot ulcers: Proof of concept study

    Get PDF
    Patients with diabetic foot ulcers have poor adherence to treatment recommendations. However, the most effective way to support adherence in this population is unknown. This study aimed to assess the preliminary effectiveness of a motivation communication training programme for healthcare professionals working with these patients, using theory and evidence-based strategies.A proof-of-concept study using a non-randomised, controlled before-and-after design. Six podiatrists took part in the motivation communication training programme. Pre-training, observation was undertaken to examine the communication style currently used by podiatrists in routine consultations. Patientsā€™ (n = 25) perceptions of podiatrist autonomy support, self-determination for limiting weight-bearing activity and average daily step count were also assessed. Post training, observations and patient measures were repeated with a different group of patients (n = 24). Observations indicated that podiatrists exhibited a more need-supportive communication style (e.g., taking time to understand patientsā€™ perspectives) after undergoing the training programme. Patients in the post-training group reported higher levels of autonomy support, while self-determination to limit weight-bearing activity remained unchanged. Although the post-training group had a lower average daily step count, the difference was not statistically significant. This is the first study to investigate implementation of motivation communication strategies in routine consultations with patients with diabetic foot ulcers. Results suggest that training can enhance healthcare professionalsā€™ motivation communication skills with potential for addressing adherence issues, however, a larger cluster randomised controlled trial is necessary to confirm this
    • ā€¦
    corecore