397 research outputs found

    Decoration of the truncated tetrahedron - an Archimedean polyhedron - to produce a new class of convex equilateral polyhedra with tetrahedral symmetry

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    The Goldberg construction of symmetric cages involves pasting a patch cut out of a regular tiling onto the faces of a Platonic host polyhedron, resulting in a cage with the same symmetry as the host. For example, cutting equilateral triangular patches from a 6.6.6 tiling of hexagons and pasting them onto the full triangular faces of an icosahedron produces icosahedral fullerene cages. Here we show that pasting cutouts from a 6.6.6 tiling onto the full hexagonal and triangular faces of an Archimedean host polyhedron, the truncated tetrahedron, produces two series of tetrahedral (T-d) fullerene cages. Cages in the first series have 28n(2) vertices (n >= 1). Cages in the second (leapfrog) series have 3 x 28n(2). We can transform all of the cages of the first series and the smallest cage of the second series into geometrically convex equilateral polyhedra. With tetrahedral (T-d) symmetry, these new polyhedra constitute a new class of "convex equilateral polyhedra with polyhedral symmetry". We also show that none of the other Archimedean polyhedra, six with octahedral symmetry and six with icosahedral, can host full-face cutouts from regular tilings to produce cages with the host's polyhedral symmetry

    Relationship between trauma, psychological distress and help-seeking among corrective service workers

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    Background: Corrective service workers (CSWs) are at high risk of post-traumatic stress disorder (PTSD) and other mental health problems. Prevalence rates and help-seeking behaviours are under-researched within this population. Aims: To assess rates of PTSD and distress, and identify predictors of intention to seek help, among workers at an Australian corrective service agency. Methods: A cross-sectional online survey was used to collect data on staff demographics, employment, PTSD symptoms and current distress. Participants received a tailored feedback report including referral to relevant mental health services (where applicable) and were asked to indicate their likelihood of seeking help. Prevalence data are reported. Binary logistic regression was used to examine relationships between participant characteristics and help-seeking for those with probable PTSD and/or high psychological distress. Results: Participants (n=1001) were predominantly men (56.8%) with a mean age of 46.72 (SD=11.00). Over half (58.0%) were classified as probable PTSD cases, and one-third (33.0%) were experiencing high psychological distress. Around a third (34.3%) of participants with probable PTSD and/or elevated distress indicated they were likely to seek help. Older age and fewer years of service were associated with increased help-seeking intentions. Conclusions: CSWs were found to be experiencing probable PTSD at higher rates than reported in previous studies. Relatively few intended to seek help from mental health services, despite being provided with personalised screening and feedback along with access to specialised care. Future research should investigate the potential role of organisational support as a facilitator of help-seeking within this population

    Asymptotic solution of the low Reynolds-number flow between two co-axial cones of common apex

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    The paper is concerned with the axi-symmetrlc, incompressible, steady, laminar and Newtonian flow between two, stationary, conical-boundaries, which exhibit a common apex but may include arbitrary angles. The flow pattern and pressure field are obtained by solving the pertinent Navier-Stokes' equations in the spherical coordinate system. The solution is presented in the form of an asymptotic series, which converges towards the creeping flow solution as a cross-sectional Reynolds-number tends to zero. The first term in the series, namely the creeping flow solution, is given in closed form; whereas, higher order terms contain functions which generally could only be expressed in infinite series form, or else evaluated numerically. Some of the results obtained for converging and diverging flows are displayed and they are demonstrated to be plausible and informative

    Smartphone application for preventing depression: Study protocol for a workplace randomised controlled trial

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    © Author(s) (or their employer(s)) 2018. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ. Introduction Depression is the leading cause of life years lost due to disability. Appropriate prevention has the potential to reduce the incidence of new cases of depression, however, traditional prevention approaches face significant scalability issues. Prevention programmes delivered by via smartphone applications provide a potential solution. The workplace is an ideal setting to roll out this form of intervention, particularly among industries that are unlikely to access traditional health initiatives and whose workplace characteristics create accessibility and portability issues. The study aims to evaluate the effectiveness of a smartphone application designed to prevent depression and improve well-being. The effectiveness of the app as a universal, selective and indicated prevention tool will also be evaluated. Methods and analysis A multicentre randomised controlled trial, to determine the effectiveness of the intervention compared with an active mood monitoring control in reducing depressive symptoms (primary outcome) and the prevalence of depression at 3 months, with secondary outcomes assessing well-being and work performance. Employees from a range of industries will be invited to participate. Participants with likely current depression at baseline will be excluded. Following baseline assessment, participants, blinded to their allocation, will be randomised to receive one of two versions of the application: headgear (a 30-day mental health intervention) or a control application (mood monitoring for 30 days). Both versions of the app contain a risk calculator to provide a measure of future risk. Analyses will be conducted within an intention-To-Treat framework using mixed modelling, with additional analyses conducted to compare the moderating effect of baseline risk level and depression symptom severity on the intervention's effectiveness. Ethics and dissemination The current trial has received ethics approval from the University of New South Wales Human Research Ethics Committee (HC17021). Study results will be disseminated through peer-reviewed journals and conferences. Trial registration number ACTRN12617000548336; Results

    TrendMonitor Audiovisuele Collecties in Nederland 2022

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    Deze vierde TrendMonitor Audiovisuele Collecties in Nederland geeft een overzicht van de stand van zaken wat betreft audiovisueel materiaal bij collectionerende instellingen in Nederland. Beeld & Geluid levert als landelijk knooppunt voor de audiovisuele en mediasector binnen het Netwerk Digitaal Erfgoed een actief bijdrage aan de Nationale Digitale Strategie, in het bijzonder rondom de duurzaamheid en toegankelijkheid van media en audiovisueel erfgoed. De uitkomsten van dit onderzoek zijn richtinggevend voor zowel de activiteiten van Beeld & Geluid als die van AVA_Net, het netwerk van audiovisuele collectiehouders in Nederland. Ook dienen ze als staalkaart en graadmeter voor de gezondheid en beschikbaarheid van de geluiden en bewegende beelden die ons nationale geheugen vormen

    Basic science232. Certolizumab pegol prevents pro-inflammatory alterations in endothelial cell function

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    Background: Cardiovascular disease is a major comorbidity of rheumatoid arthritis (RA) and a leading cause of death. Chronic systemic inflammation involving tumour necrosis factor alpha (TNF) could contribute to endothelial activation and atherogenesis. A number of anti-TNF therapies are in current use for the treatment of RA, including certolizumab pegol (CZP), (Cimzia ®; UCB, Belgium). Anti-TNF therapy has been associated with reduced clinical cardiovascular disease risk and ameliorated vascular function in RA patients. However, the specific effects of TNF inhibitors on endothelial cell function are largely unknown. Our aim was to investigate the mechanisms underpinning CZP effects on TNF-activated human endothelial cells. Methods: Human aortic endothelial cells (HAoECs) were cultured in vitro and exposed to a) TNF alone, b) TNF plus CZP, or c) neither agent. Microarray analysis was used to examine the transcriptional profile of cells treated for 6 hrs and quantitative polymerase chain reaction (qPCR) analysed gene expression at 1, 3, 6 and 24 hrs. NF-κB localization and IκB degradation were investigated using immunocytochemistry, high content analysis and western blotting. Flow cytometry was conducted to detect microparticle release from HAoECs. Results: Transcriptional profiling revealed that while TNF alone had strong effects on endothelial gene expression, TNF and CZP in combination produced a global gene expression pattern similar to untreated control. The two most highly up-regulated genes in response to TNF treatment were adhesion molecules E-selectin and VCAM-1 (q 0.2 compared to control; p > 0.05 compared to TNF alone). The NF-κB pathway was confirmed as a downstream target of TNF-induced HAoEC activation, via nuclear translocation of NF-κB and degradation of IκB, effects which were abolished by treatment with CZP. In addition, flow cytometry detected an increased production of endothelial microparticles in TNF-activated HAoECs, which was prevented by treatment with CZP. Conclusions: We have found at a cellular level that a clinically available TNF inhibitor, CZP reduces the expression of adhesion molecule expression, and prevents TNF-induced activation of the NF-κB pathway. Furthermore, CZP prevents the production of microparticles by activated endothelial cells. This could be central to the prevention of inflammatory environments underlying these conditions and measurement of microparticles has potential as a novel prognostic marker for future cardiovascular events in this patient group. Disclosure statement: Y.A. received a research grant from UCB. I.B. received a research grant from UCB. S.H. received a research grant from UCB. All other authors have declared no conflicts of interes
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