604 research outputs found

    State of the art spatial visualization of the response of neovascularisation to anti-vascular endothelial growth factor therapy

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    PURPOSE: To visualize the mode of action of anti-vascular endothelial growth factor (anti-VEGFs) therapy on retinal neovascularization (RNV) in a patient with macular telangiectasia (MacTel) type 2 using a detailed three-dimensional data environment. OBSERVATION: A 60-year-old man presented with visual acuity loss and was diagnosed with MacTel type 2. Fluorescein angiography was not possible for safety reasons because of a history of severe reaction to fluorescein dye at his referring hospital. Optical coherence tomography angiography (OCTA) imaging revealed new retinal neovascular membranes (RNV) in the macula of both eyes. A marked reduction in the size of the RNV in both eyes was evident on volume-rendered three-dimensional OCTA retinal imaging after the first anti-VEGF injection. CONCLUSION AND IMPORTANCE: The ability to directly observe the effect of anti-VEGF injections on a RNV using three-dimensional OCTA was successfully demonstrated. This can be useful in patients with previous allergic and potentially lethal complications to fluorescein. In addition, enhanced three-dimensional spatial display of RNV leads to a greater understanding of the perfusion profile and the anatomical changes that occur in ocular neovascularization relative to surrounding tissue. This has the potential to provide insight into the pathobiology of angiogenesis

    MACULAR TELANGIECTASIA TYPE 2: Quantitative Analysis of a Novel Phenotype and Implications for the Pathobiology of the Disease

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    PURPOSE: To investigate retinal microcystoid spaces in macular telangiectasia type 2 with spectral domain optical coherence tomography. METHODS: Retrospective review of 135 patients enrolled in the MacTel Natural History Observation and Registry Study at Moorfields Eye Hospital, United Kingdom. One hundred seventy-two eyes from 86 patients who had a comparable scan protocol of at least 30 μm interval were included for analysis. Retinal microcystoid spaces were identified and segmented and metrics analyzed. RESULTS: From 172 eyes of 86 patients, microcystoid spaces were found in 11 eyes (6.4%) from 8 patients (9.3%). The mean number of microcystoid spaces per eye was 12.9 ± 18.2. Most were located in the inner nuclear layer. The inferonasal quadrant of the macula was the least commonly affected region. Microcystoid spaces were distributed entirely within the assumed macular telangiectasia area on blue light reflectance in all but 2 eyes (4 of 142 microcysts). The median diameter of the microcystoid spaces was 31 μm (range 15 μm-80 μm). CONCLUSION: Microcystoid spaces as a phenotype of macular telangiectasia should be considered in the differentials for microcystic edema. Understanding the pathogenesis of these lesions may provide further insight into the role of Müller cell dysfunction in this disorder

    The Action Scales Model: A conceptual tool to identify key points for action within complex adaptive systems

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    Background: Systems thinking is integral to working effectively within complex systems, such as those which drive the current population levels of overweight and obesity. It is increasingly recognised that a systems approach – which corrals public, private, voluntary and community sector organisations to make their actions and efforts coherent – is necessary to address the complex drivers of obesity. Identifying, implementing and evaluating actions within complex adaptive systems is challenging, and may differ from previous approaches used in public health. Methods: Within this conceptual article, we present the Action Scales Model (ASM). The ASM is a simple tool to help policymakers, practitioners and evaluators to conceptualise, identify and appraise actions within complex adaptive systems. We developed this model using our collective expertise and experience in working with local government authority stakeholders on the Public Health England Whole Systems Obesity programme. It aligns with, and expands upon, previous models such as the Intervention Level Framework, the Iceberg Model and Donella Meadows’ 12 places to intervene within a system. Results: The ASM describes four levels (synonymous with leverage points) to intervene within a system, with deeper levels providing greater potential for changing how the system functions. Levels include events, structures, goals and beliefs. We also present how the ASM can be used to support practice and policy, and finish by highlighting its utility as an evaluative aid. Discussion: This practical tool was designed to support those working at the front line of systems change efforts, and while we use the population prevalence of obesity as an outcome of a complex adaptive system, the ASM and the associated principles can be applied to other issues. We hope that the ASM encourages people to think differently about the systems that they work within and to identify new and potentially more impactful opportunities to leverage change

    Volume rendering of superficial optic disc drusen: A possible new imaging technique using optical coherence tomography angiography

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    BACKGROUND: Optic disc drusen (ODD) are calcified deposits potentially caused by disturbances in axonal metabolism. The clinical course and visual impairment of ODD is usually mild; however, significant ocular morbidity may occur, such as visual field defects and retinal haemorrhages. Optic disc drusen may pose a diagnostic dilemma and differentiating these from other entities that can lead to similar compressive axonal distress is imperative. We present a novel technique for three-dimensional (3D) characterisation of superficial ODD based on 3D volume rendering of optical coherence tomography angiography (3DOCTA) scans. MATERIAL AND METHODS: Optical coherence tomography (Cirrus™ HD-OCT Model 5000 with AngioPlex, Carl Zeiss Meditec, Inc., Dublin, USA) scans were obtained from the optic nerve head of a healthy 22-year-old female. Consequently, 3D structural OCT data and OCTA were analysed, enabling ODD segmentation and spatial characterization. RESULTS: Volumetric analysis of superficial ODD showed a maximal drusen horizontal diameter of 223 μm, maximal vertical diameter of 268 μm, surface area of 6617 μm 2 and volume measurement of 12,875 μm 3. The drusen were characterised by a connected network of multiple drusen islands instead of forming a dense mass. Multiple vascular channels with perforating vessels were found across the drusen. CONCLUSION: Three-dimensional volume rendering of OCTA scans provided new insight on the spatio-anatomical features of superficial ODD. The new features herein described, namely multilobulated drusen islands and intradrusen channels, may directly contribute to the pathogenic events leading to transient non-embolic visual loss and small vessel occlusion secondary to ODD

    Multidimensional sexual perfectionism and female sexual function: A longitudinal investigation

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    Research on multidimensional sexual perfectionism differentiates four forms of sexual perfectionism: self-oriented, partner-oriented, partner-prescribed, and socially prescribed. Self-oriented sexual perfectionism reflects perfectionistic standards people apply to themselves as sexual partners; partner-oriented sexual perfectionism reflects perfectionistic standards people apply to their sexual partner; partner-prescribed sexual perfectionism reflects people’s beliefs that their sexual partner imposes perfectionistic standards on them; and socially prescribed sexual perfectionism reflects people’s beliefs that society imposes such standards on them. Previous studies found partner-prescribed and socially prescribed sexual perfectionism to be maladaptive forms of sexual perfectionism associated with a negative sexual self-concept and problematic sexual behaviors, but only examined cross-sectional relationships. The present article presents the first longitudinal study examining whether multidimensional sexual perfectionism predicts changes in sexual self-concept and sexual function over time. A total of 366 women aged 17-69 years completed measures of multidimensional sexual perfectionism, sexual esteem, sexual anxiety, sexual problem self-blame, and female sexual function (cross-sectional data). Three to six months later, 164 of the women completed the same measures again (longitudinal data). Across analyses, partner-prescribed sexual perfectionism emerged as the most maladaptive form of sexual perfectionism. In the cross-sectional data, partner-prescribed sexual perfectionism showed positive relationships with sexual anxiety, sexual problem self-blame, and intercourse pain and negative relationships with sexual esteem, desire, arousal, lubrication, and orgasmic function. In the longitudinal data, partner-prescribed sexual perfectionism predicted increases in sexual anxiety and decreases in sexual esteem, arousal, and lubrication over time. The findings suggest that partner-prescribed sexual perfectionism contributes to women’s negative sexual self-concept and female sexual dysfunction

    Infrared composition of the Large Magellanic Cloud

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    The evolution of galaxies and the history of star formation in the Universe are among the most important topics in today's astrophysics. Especially, the role of small, irregular galaxies in the star-formation history of the Universe is not yet clear. Using the data from the AKARI IRC survey of the Large Magellanic Cloud at 3.2, 7, 11, 15, and 24 {\mu}m wavelengths, i.e., at the mid- and near-infrared, we have constructed a multiwavelength catalog containing data from a cross-correlation with a number of other databases at different wavelengths. We present the separation of different classes of stars in the LMC in color-color, and color-magnitude, diagrams, and analyze their contribution to the total LMC flux, related to point sources at different infrared wavelengths

    A plague on five of your houses - statistical re-assessment of three pneumonic plague outbreaks that occurred in Suffolk, England, between 1906 and 1918

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    <p>Abstract</p> <p>Background</p> <p>Plague is a re-emerging disease and its pneumonic form is a high priority bio-terrorist threat. Epidemiologists have previously analysed historical outbreaks of pneumonic plague to better understand the dynamics of infection, transmission and control. This study examines 3 relatively unknown outbreaks of pneumonic plague that occurred in Suffolk, England, during the first 2 decades of the twentieth century.</p> <p>Methods</p> <p>The Kolmogorov-Smirnov statistical test is used to compare the symptomatic period and the length of time between successive cases (i.e. the serial interval) with previously reported values. Consideration is also given to the case fatality ratio, the average number of secondary cases resulting from each primary case in the observed minor outbreaks (termed <it>R</it><sub><it>minor</it></sub>), and the proportion of individuals living within an affected household that succumb to pneumonic plague via the index case (i.e. the household secondary attack rate (SAR)).</p> <p>Results</p> <p>2 of the 14 cases survived giving a case fatality ratio of 86% (95% confidence interval (CI) = {57%, 98%}). For the 12 fatal cases, the average symptomatic period was 3.3 days (standard deviation (SD) = 1.2 days) and, for the 11 non index cases, the average serial interval was 5.8 days (SD = 2.0 days). <it>R</it><sub><it>minor </it></sub>was calculated to be 0.9 (SD = 1.0) and, in 2 households, the SAR was approximately 14% (95% CI = {0%, 58%}) and 20% (95% CI = {1%, 72%}), respectively.</p> <p>Conclusions</p> <p>The symptomatic period was approximately 1 day longer on average than in an earlier study but the serial interval was in close agreement with 2 previously reported values. 2 of the 3 outbreaks ended without explicit public health interventions; however, non-professional caregivers were particularly vulnerable - an important public health consideration for any future outbreak of pneumonic plague.</p

    Violent video games in virtual reality : re-evaluating the impact and rating of interactive experiences

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    Bespoke Virtual Reality (VR) laboratory experiences can be differently affecting than traditional display experiences. With the proliferation of at-home VR headsets, these effects need to be explored in consumer media, to ensure the public are adequately informed. As yet, the organizations responsible for content descrip-tions and age-based ratings of consumer content do not rate VR games differently to those played on TV. This could lead to experiences that are more intense or subconsciously affecting than desired. To test whether VR and non-VR games are differently affecting, and so whether game ratings are appropriate, our research examined how participant (n=16) experience differed when playing the violent horror video game “Resident Evil 7”, viewed from a first-person perspective in PlayStation VR and on a 40” TV. The two formats led to meaningfully different experiences, suggesting that current game ratings may be unsuitable for capturing and conveying VR experiences
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