126 research outputs found

    Choosing wisely? Quantifying the extent of three low value psychotropic prescribing practices in Australia

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    BACKGROUND:The global Choosing Wisely campaign has identified the following psychotropic prescribing as low-value (harmful or wasteful): (1) benzodiazepine use in the elderly, (2) antipsychotic use in dementia and (3) prescribing two or more antipsychotics concurrently. We aimed to quantify the extent of these prescribing practices in the Australian population. METHODS:We applied indicators to dispensing claims of a 10% random sample of Australian Pharmaceutical Benefits Scheme beneficiaries to quantify annual rates of each low-value practice from 2013 to 2016. We also assessed patient factors and direct medicine costs (extrapolated to the entire Australian population) associated with each practice in 2016. RESULTS:We observed little change in the rates of the three practices between 2013 and 2016. In 2016, 15.3% of people aged ≥65 years were prescribed a benzodiazepine, 0.5% were prescribed antipsychotics in the context of dementia and 0.2% of people aged ≥18 years received two or more antipsychotics concurrently. The likelihood of elderly people receiving benzodiazepines or antipsychotics in the context of dementia increased with age and the likelihood of receiving all three practices increased with comorbidity burden. In 2016, direct medicine costs to the government of all three practices combined, extrapolated to national figures, were > $21 million AUD. CONCLUSIONS:Our indicators suggest that the frequency of these three practices has not changed appreciably in recent years and that they incur significant costs. Worryingly, people with the greatest risk of harm from these prescribing practices are often the most likely to receive them.Jonathan Brett, Helga Zoega, Nicholas A. Buckley, Benjamin J. Daniels, Adam G. Elshaug and Sallie-Anne Pearso

    Modal scattering at an impedance transition in a lined flow duct

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    An explicit Wiener-Hopf solution is derived to describe the scattering of duct modes at a hard-soft wall impedance transition in a circular duct with uniform mean flow. Specifically, we have a circular duct r = 1,-8 <x <8 with mean flow Mach number M > 0 and a hard wall along x <0 and a wall of impedance Z along x > 0. A minimum edge condition at x = 0 requires a continuous wall streamline r = 1 + h(x, t ), no more singular than h = O(x1/2) for x ¿ 0. A mode, incident from x <0, scatters at x = 0 into a series of reflected modes and a series of transmitted modes. Of particular interest is the role of a possible instability along the lined wall in combination with the edge singularity. If one of the "upstream" running modes is to be interpreted as a downstream-running instability, we have an extra degree of freedom in the Wiener-Hopf analysis that can be resolved by application of some form of Kutta condition at x = 0, for example a more stringent edge condition where h = O(x3/2) at the downstream side. The question of the instability requires an investigation of the modes in the complex frequency plane and therefore depends on the chosen impedance model, since Z = Z(¿) is essentially frequency dependent. The usual causality condition by Briggs and Bers appears to be not applicable here because it requires a temporal growth rate bounded for all real axial wave numbers. The alternative Crighton-Leppington criterion, however, is applicable and confirms that the suspected mode is usually unstable. In general, the effect of this Kutta condition is significant, but it is particularly large for the plane wave at low frequencies and should therefore be easily measurable. For ¿ ¿ 0, the modulus tends to |R001| ¿ (1 + M)/(1 - M) without and to 1 with Kutta condition, while the end correction tends to8without and to a finite value with Kutta condition. This is exactly the same behaviour as found for reflection at a pipe exit with flow, irrespective if this is uniform or jet flow

    Random Convex Hulls and Extreme Value Statistics

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    In this paper we study the statistical properties of convex hulls of NN random points in a plane chosen according to a given distribution. The points may be chosen independently or they may be correlated. After a non-exhaustive survey of the somewhat sporadic literature and diverse methods used in the random convex hull problem, we present a unifying approach, based on the notion of support function of a closed curve and the associated Cauchy's formulae, that allows us to compute exactly the mean perimeter and the mean area enclosed by the convex polygon both in case of independent as well as correlated points. Our method demonstrates a beautiful link between the random convex hull problem and the subject of extreme value statistics. As an example of correlated points, we study here in detail the case when the points represent the vertices of nn independent random walks. In the continuum time limit this reduces to nn independent planar Brownian trajectories for which we compute exactly, for all nn, the mean perimeter and the mean area of their global convex hull. Our results have relevant applications in ecology in estimating the home range of a herd of animals. Some of these results were announced recently in a short communication [Phys. Rev. Lett. {\bf 103}, 140602 (2009)].Comment: 61 pages (pedagogical review); invited contribution to the special issue of J. Stat. Phys. celebrating the 50 years of Yeshiba/Rutgers meeting

    Effectiveness and tolerability of 12-Month Brivaracetam in the real world: EXPERIENCE, an international pooled analysis of individual patient records

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    Background and Objective Real-world evidence studies of brivaracetam (BRV) have been restricted in scope, location, and patient numbers. The objective of this pooled analysis was to assess effectiveness and tolerability of brivaracetam (BRV) in routine practice in a large international population. Methods EXPERIENCE/EPD332 was a pooled analysis of individual patient records from multiple independent non-interventional studies of patients with epilepsy initiating BRV in Australia, Europe, and the United States. Eligible study cohorts were identified via a literature review and engagement with country lead investigators, clinical experts, and local UCB Pharma scientific/medical teams. Included patients initiated BRV no earlier than January 2016 and no later than December 2019, and had ≥ 6 months of follow-up data. The databases for each cohort were reformatted and standardised to ensure information collected was consistent. Outcomes included ≥ 50% reduction from baseline in seizure frequency, seizure freedom (no seizures within 3 months before timepoint), continuous seizure freedom (no seizures from baseline), BRV discontinuation, and treatment-emergent adverse events (TEAEs) at 3, 6, and 12 months. Patients with missing data after BRV discontinuation were considered non-responders/not seizure free. Analyses were performed for all adult patients (≥ 16 years), and for subgroups by seizure type recorded at baseline; by number of prior antiseizure medications (ASMs) at index; by use of BRV as monotherapy versus polytherapy at index; for patients who switched from levetiracetam to BRV versus patients who switched from other ASMs to BRV; and for patients with focal-onset seizures and a BRV dose of ≤ 200 mg/day used as add-on at index. Analysis populations included the full analysis set (FAS; all patients who received at least one BRV dose and had seizure type and age documented at baseline) and the modified FAS (all FAS patients who had at least one seizure recorded during baseline). The FAS was used for all outcomes other than ≥ 50% seizure reduction. All outcomes were summarised using descriptive statistics. Results Analyses included 1644 adults. At baseline, 72.0% were 16–49 years of age and 92.2% had focal-onset seizures. Patients had a median (Q1, Q3) of 5.0 (2.0, 8.0) prior antiseizure medications at index. At 3, 6, and 12 months, respectively, ≥ 50% seizure reduction was achieved by 32.1% (n = 619), 36.7% (n = 867), and 36.9% (n = 822) of patients; seizure freedom rates were 22.4% (n = 923), 17.9% (n = 1165), and 14.9% (n = 1111); and continuous seizure freedom rates were 22.4% (n = 923), 15.7% (n = 1165), and 11.7% (n = 1111). During the whole study follow-up, 551/1639 (33.6%) patients discontinued BRV. TEAEs since prior visit were reported in 25.6% (n = 1542), 14.2% (n = 1376), and 9.3% (n = 1232) of patients at 3, 6, and 12 months, respectively. Conclusions This pooled analysis using data from a variety of real-world settings suggests BRV is effective and well tolerated in routine clinical practice in a highly drug-resistant patient population

    Fire as a fundamental ecological process: Research advances and frontiers

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    Fire is a powerful ecological and evolutionary force that regulates organismal traits, population sizes, species interactions, community composition, carbon and nutrient cycling and ecosystem function. It also presents a rapidly growing societal challenge, due to both increasingly destructive wildfires and fire exclusion in fire‐dependent ecosystems. As an ecological process, fire integrates complex feedbacks among biological, social and geophysical processes, requiring coordination across several fields and scales of study. Here, we describe the diversity of ways in which fire operates as a fundamental ecological and evolutionary process on Earth. We explore research priorities in six categories of fire ecology: (a) characteristics of fire regimes, (b) changing fire regimes, (c) fire effects on above‐ground ecology, (d) fire effects on below‐ground ecology, (e) fire behaviour and (f) fire ecology modelling. We identify three emergent themes: the need to study fire across temporal scales, to assess the mechanisms underlying a variety of ecological feedbacks involving fire and to improve representation of fire in a range of modelling contexts. Synthesis : As fire regimes and our relationships with fire continue to change, prioritizing these research areas will facilitate understanding of the ecological causes and consequences of future fires and rethinking fire management alternatives

    Cloaked websites: propaganda, cyber-racism and epistemology in the digital era

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    This article analyzes cloaked websites, which are sites published by individuals or groups who conceal authorship in order to disguise deliberately a hidden political agenda. Drawing on the insights of critical theory and the Frankfurt School, this article examines the way in which cloaked websites conceal a variety of political agendas from a range of perspectives. Of particular interest here are cloaked white supremacist sites that disguise cyber-racism. The use of cloaked websites to further political ends raises important questions about knowledge production and epistemology in the digital era. These cloaked sites emerge within a social and political context in which it is increasingly difficult to parse fact from propaganda, and this is a particularly pernicious feature when it comes to the cyber-racism of cloaked white supremacist sites. The article concludes by calling for the importance of critical, situated political thinking in the evaluation of cloaked websites

    SARS-CoV-2-specific nasal IgA wanes 9 months after hospitalisation with COVID-19 and is not induced by subsequent vaccination

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    BACKGROUND: Most studies of immunity to SARS-CoV-2 focus on circulating antibody, giving limited insights into mucosal defences that prevent viral replication and onward transmission. We studied nasal and plasma antibody responses one year after hospitalisation for COVID-19, including a period when SARS-CoV-2 vaccination was introduced. METHODS: In this follow up study, plasma and nasosorption samples were prospectively collected from 446 adults hospitalised for COVID-19 between February 2020 and March 2021 via the ISARIC4C and PHOSP-COVID consortia. IgA and IgG responses to NP and S of ancestral SARS-CoV-2, Delta and Omicron (BA.1) variants were measured by electrochemiluminescence and compared with plasma neutralisation data. FINDINGS: Strong and consistent nasal anti-NP and anti-S IgA responses were demonstrated, which remained elevated for nine months (p < 0.0001). Nasal and plasma anti-S IgG remained elevated for at least 12 months (p < 0.0001) with plasma neutralising titres that were raised against all variants compared to controls (p < 0.0001). Of 323 with complete data, 307 were vaccinated between 6 and 12 months; coinciding with rises in nasal and plasma IgA and IgG anti-S titres for all SARS-CoV-2 variants, although the change in nasal IgA was minimal (1.46-fold change after 10 months, p = 0.011) and the median remained below the positive threshold determined by pre-pandemic controls. Samples 12 months after admission showed no association between nasal IgA and plasma IgG anti-S responses (R = 0.05, p = 0.18), indicating that nasal IgA responses are distinct from those in plasma and minimally boosted by vaccination. INTERPRETATION: The decline in nasal IgA responses 9 months after infection and minimal impact of subsequent vaccination may explain the lack of long-lasting nasal defence against reinfection and the limited effects of vaccination on transmission. These findings highlight the need to develop vaccines that enhance nasal immunity. FUNDING: This study has been supported by ISARIC4C and PHOSP-COVID consortia. ISARIC4C is supported by grants from the National Institute for Health and Care Research and the Medical Research Council. Liverpool Experimental Cancer Medicine Centre provided infrastructure support for this research. The PHOSP-COVD study is jointly funded by UK Research and Innovation and National Institute of Health and Care Research. The funders were not involved in the study design, interpretation of data or the writing of this manuscript

    Effects of elevated CO2 and trace ethylene present throughout the storage season on the processing colour of stored potatoes

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    Previous short-term trials (9-week duration) have shown that the fry colour of stored potatoes (Solanum tuberosum L.) can be negatively affected by simultaneous exposure to elevated CO2 plus a trace concentration of ethylene gas. In the present study, trials were conducted during each of two storage seasons (2008–2009 and 2009–2010), to examine the effects of long-term exposure to these two gases during the entire November to June storage season. In each year, 0 or 2 kPa CO2 and 0 or 0.5 µl l-1 ethylene were applied in a factorial design to tubers of four processing cultivars (Russet Burbank, Shepody, Innovator and Dakota Pearl). Processing colour of the tubers was evaluated at the start of each trial and at intervals of 4 weeks thereafter. In the three French fry cultivars (i.e. Russet Burbank, Shepody and Innovator), the fry colour of tubers exposed to CO2¿+¿ethylene together was darker than the controls. In the chipping cultivar Dakota Pearl, the gas treatments had only a small effect on chip colour. Fry colour darkening due to an interaction of CO2¿×¿ethylene¿×¿time was significant only in Innovator. Processing colour of all cultivars was darkened by these gases, but the magnitude and timing of the responses varied widely between gases, among cultivars and from the start to the end of the season
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