147 research outputs found

    Distributed high-fidelity graphics using P2P

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    In the field of three-dimensional computer graphics, rendering refers to the process of generating images of a scene from a particular viewpoint. There are many different ways to do this, from the highly interactive real-time rendering methods to the more photorealistic and computationally intensive methods. This work is concerned with Physically Based Rendering (PBR), a class of rendering algorithms capable of achieving a very high level of realism. This is achievable thanks to physically accurate modelling of the way light interacts with objects in a scene, together with the use of accurately modelled materials and physical quantities.peer-reviewe

    An Open-Publishing Response to the COVID-19 Infodemic

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    The COVID-19 pandemic catalyzed the rapid dissemination of papers and preprints investigating the disease and its associated virus, SARS-CoV-2. The multifaceted nature of COVID-19 demands a multidisciplinary approach, but the urgency of the crisis combined with the need for social distancing measures present unique challenges to collaborative science. We applied a massive online open publishing approach to this problem using Manubot. Through GitHub, collaborators summarized and critiqued COVID-19 literature, creating a review manuscript. Manubot automatically compiled citation information for referenced preprints, journal publications, websites, and clinical trials. Continuous integration workflows retrieved up-to-date data from online sources nightly, regenerating some of the manuscript\u27s figures and statistics. Manubot rendered the manuscript into PDF, HTML, LaTeX, and DOCX outputs, immediately updating the version available online upon the integration of new content. Through this effort, we organized over 50 scientists from a range of backgrounds who evaluated over 1,500 sources and developed seven literature reviews. While many efforts from the computational community have focused on mining COVID-19 literature, our project illustrates the power of open publishing to organize both technical and non-technical scientists to aggregate and disseminate information in response to an evolving crisis

    Multimodality in galaxy clusters from SDSS DR8: substructure and velocity distribution

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    We search for the presence of substructure, a non-Gaussian, asymmetrical velocity distribution of galaxies, and large peculiar velocities of the main galaxies in galaxy clusters with at least 50 member galaxies, drawn from the SDSS DR8. We employ a number of 3D, 2D, and 1D tests to analyse the distribution of galaxies in clusters: 3D normal mixture modelling, the Dressler-Shectman test, the Anderson-Darling and Shapiro-Wilk tests and others. We find the peculiar velocities of the main galaxies, and use principal component analysis to characterise our results. More than 80% of the clusters in our sample have substructure according to 3D normal mixture modelling, the Dressler-Shectman (DS) test shows substructure in about 70% of the clusters. The median value of the peculiar velocities of the main galaxies in clusters is 206 km/s (41% of the rms velocity). The velocities of galaxies in more than 20% of the clusters show significant non-Gaussianity. While multidimensional normal mixture modelling is more sensitive than the DS test in resolving substructure in the sky distribution of cluster galaxies, the DS test determines better substructure expressed as tails in the velocity distribution of galaxies. Richer, larger, and more luminous clusters have larger amount of substructure and larger (compared to the rms velocity) peculiar velocities of the main galaxies. Principal component analysis of both the substructure indicators and the physical parameters of clusters shows that galaxy clusters are complicated objects, the properties of which cannot be explained with a small number of parameters or delimited by one single test. The presence of substructure, the non-Gaussian velocity distributions, as well as the large peculiar velocities of the main galaxies, shows that most of the clusters in our sample are dynamically young.Comment: 15 pages, 11 figures, 2 online tables, accepted for publication in Astronomy and Astrophysic

    Implementation of the reverse screening syphilis algorithm in a clinical laboratory

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    Background: Syphilis remains a public health concern worldwide, the accuracy of diagnostic tests is critical for its successful control. Currently, there are two approaches to the diagnosis of syphilis using serological tests: the traditional algorithm and the reverse algorithm. Aim: The goal of this study was to analyse the advantages and disadvantages in the implementation of the syphilis reverse-screening algorithm in an outpatient clinical laboratory. Methods: An observational cross-sectional study was carried out analyzing 246 reactive sera from a total of 14700 requests for syphilis serology. Chemiluminescent assay ARCHITECT Syphilis TP, V.D.R.L. and FTA-Abs were performed. Results: Among 246 reactive sera by ARCHITECT Syphilis TP, 129 were reactive and 117 were non-reactive by V.D.R.L. the last mentioned resulted in 97 reactive and 20 non-reactive by FTA-Abs, suggesting false positives (0.13%).Two patients with primary infection were detected, that were not detected by V.D.R.L. and one pregnant woman with primary infection with a high value S/CO and V.D.R.L.:1 dils. Conclusions: Among the advantages of using a reverse algorithm were greater sensitivity in the detection of patients with primary syphilis; automation, complete traceability of the samples; objective interpretation and conclusive results.Facultad de Ciencias Exacta

    Framework for managing the COVID-19 infodemic : Methods and results of an online, crowdsourced WHO technical consultation

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    Background: An infodemic is an overabundance of information—some accurate and some not—that occurs during an epidemic. In a similar manner to an epidemic, it spreads between humans via digital and physical information systems. It makes it hard for people to find trustworthy sources and reliable guidance when they need it. Objective: A World Health Organization (WHO) technical consultation on responding to the infodemic related to the coronavirus disease (COVID-19) pandemic was held, entirely online, to crowdsource suggested actions for a framework for infodemic management. Methods: A group of policy makers, public health professionals, researchers, students, and other concerned stakeholders was joined by representatives of the media, social media platforms, various private sector organizations, and civil society to suggest and discuss actions for all parts of society, and multiple related professional and scientific disciplines, methods, and technologies. A total of 594 ideas for actions were crowdsourced online during the discussions and consolidated into suggestions for an infodemic management framework. Results: The analysis team distilled the suggestions into a set of 50 proposed actions for a framework for managing infodemics in health emergencies. The consultation revealed six policy implications to consider. First, interventions and messages must be based on science and evidence, and must reach citizens and enable them to make informed decisions on how to protect themselves and their communities in a health emergency. Second, knowledge should be translated into actionable behavior-change messages, presented in ways that are understood by and accessible to all individuals in all parts of all societies. Third, governments should reach out to key communities to ensure their concerns and information needs are understood, tailoring advice and messages to address the audiences they represent. Fourth, to strengthen the analysis and amplification of information impact, strategic partnerships should be formed across all sectors, including but not limited to the social media and technology sectors, academia, and civil society. Fifth, health authorities should ensure that these actions are informed by reliable information that helps them understand the circulating narratives and changes in the flow of information, questions, and misinformation in communities. Sixth, following experiences to date in responding to the COVID-19 infodemic and the lessons from other disease outbreaks, infodemic management approaches should be further developed to support preparedness and response, and to inform risk mitigation, and be enhanced through data science and sociobehavioral and other research. Conclusions: The first version of this framework proposes five action areas in which WHO Member States and actors within society can apply, according to their mandate, an infodemic management approach adapted to national contexts and practices. Responses to the COVID-19 pandemic and the related infodemic require swift, regular, systematic, and coordinated action from multiple sectors of society and government. It remains crucial that we promote trusted information and fight misinformation, thereby helping save lives.peer-reviewe

    The Atacama Cosmology Telescope: Data Characterization and Map Making

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    We present a description of the data reduction and mapmaking pipeline used for the 2008 observing season of the Atacama Cosmology Telescope (ACT). The data presented here at 148 GHz represent 12% of the 90 TB collected by ACT from 2007 to 2010. In 2008 we observed for 136 days, producing a total of 1423 hours of data (11 TB for the 148 GHz band only), with a daily average of 10.5 hours of observation. From these, 1085 hours were devoted to a 850 deg^2 stripe (11.2 hours by 9.1 deg) centered on a declination of -52.7 deg, while 175 hours were devoted to a 280 deg^2 stripe (4.5 hours by 4.8 deg) centered at the celestial equator. We discuss sources of statistical and systematic noise, calibration, telescope pointing, and data selection. Out of 1260 survey hours and 1024 detectors per array, 816 hours and 593 effective detectors remain after data selection for this frequency band, yielding a 38% survey efficiency. The total sensitivity in 2008, determined from the noise level between 5 Hz and 20 Hz in the time-ordered data stream (TOD), is 32 micro-Kelvin sqrt{s} in CMB units. Atmospheric brightness fluctuations constitute the main contaminant in the data and dominate the detector noise covariance at low frequencies in the TOD. The maps were made by solving the least-squares problem using the Preconditioned Conjugate Gradient method, incorporating the details of the detector and noise correlations. Cross-correlation with WMAP sky maps, as well as analysis from simulations, reveal that our maps are unbiased at multipoles ell > 300. This paper accompanies the public release of the 148 GHz southern stripe maps from 2008. The techniques described here will be applied to future maps and data releases.Comment: 20 pages, 18 figures, 6 tables, an ACT Collaboration pape

    2013 ACC/AHA guideline on the assessment of cardiovascular risk: A report of the American College of Cardiology/American heart Association Task Force on Practice Guidelines

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    1.1. Organization of the Work Group: The Risk Assessment Work Group (Work Group) was composed of 11 members and 5 ex-officio members, including internists, cardiologists, endocrinologists, and experts in cardiovascular epidemiology, biostatistics, healthcare management and economics, and guideline development. 1.2. Document Review and Approval: A formal peer review process, which included 12 expert reviewers and representatives of federal agencies, was initially completed under the auspices of the NHLBI. This document was also reviewed by 3 expert reviewers nominated by the ACC and the AHA when the management of the guideline transitioned to the ACC/AHA. The ACC and AHA Reviewers’ RWI information is published in this document (Appendix 2). This document was approved for publication by the governing bodies of the ACC and AHA and endorsed by the American Association of Cardiovascular and Pulmonary Rehabilitation, American Society for Preventive Cardiology, American Society of Hypertension, Association of Black Cardiologists, National Lipid Association, Preventive Cardiovascular Nurses Association, and WomenHeart: The National Coalition for Women With Heart Disease. 1.3. Charge to the Work Group: The Work Group was 1 of 3 work groups appointed by the NHLBI to develop its own recommendations and provide cross-cutting input to 3 Panels for updating guidelines on blood cholesterol, blood pressure (BP), and overweight/obesity. The Work Group was asked to examine the scientific evidence on risk assessment for initial ASCVD events and to develop an approach for quantitative risk assessment that could be used in practice and used or adapted by the risk factor panels (blood cholesterol, hypertension, and obesity) in their guidelines and algorithms. Specifically, the Work Group was charged with 2 tasks: 1) To develop or recommend an approach to quantitative risk assessment that could be used to guide care; and 2) To use systematic review methodology to pose and address a small number of questions judged to be critical to refining and adopting risk assessment in clinical practice

    Características clínico-epidemiológicas de pacientes hipertensos en un Consultorio Médico de Santa Clara

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    High blood pressure is a chronic non-transmittable disease, which is also a risk factor for the development of other clinical conditions. The incidence of arterial hypertension in the Cuban population is high.Aim: to characterize the evolution of arterial hypertension in a Family Doctor's Office.Methods: an observational, descriptive and cross-sectional study was carried out at the Family Doctor's Office 17-19 in the municipality of Santa Clara. The study covered the months of January to March 2020. Of the 256 hypertensive patients, a sample of 52 was selected by a simple random method.Results: Males predominated (53.84 %), together with the age group between 40 and 49 years (28.84 %). A total of 63.46 % of the patients were white-skinned. 51.61% presented risk factors. The risk factors with the highest incidence were smoking, followed by obesity and sedentary lifestyle.Conclusions: the most affected hypertensive patients are male. Most patients have a family history of high blood pressure. Smoking is a high incidence risk factor in the hypertensive population.Introducción: la hipertensión arterial es una enfermedad crónica no transmisible, que a la vez constituye un factor de riesgo para el desarrollo de otras enfermedades. La incidencia de la hipertensión arterial en la población de Cuba es alta.Objetivo: caracterizar el comportamiento de la hipertensión arterial en un Consultorio Médico de Familia.Métodos: se realizó un estudio observacional, descriptivo y transversal en el Consultorio Médico de Familia 17-19 del municipio Santa Clara. El período de estudio comprendió los meses de enero a marzo del 2020. La población fue de 256 hipertensos y se escogió una muestra de 52 hipertensos por muestreo aleatorio simple.Resultados: predominó el sexo masculino (53,84 %), y el grupo de edad entre 40 y 49 años (28,84 %). El 63,46 % de los pacientes fueron de color de la piel blanca. El 51,61 % presentaron factores de riesgo. Los factores de riesgo de mayor incidencia fueron el tabaquismo, seguido por la obesidad y el sedentarismo.Conclusiones: los pacientes hipertensos más afectados son los del sexo masculino. La mayor parte de los pacientes tienen antecedentes familiares de hipertensión arterial. El tabaquismo es un factor de riesgo de alta incidencia en la población hipertensa

    Race/Ethnic Differences in the Associations of the Framingham Risk Factors with Carotid IMT and Cardiovascular Events

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    Background: Clinical manifestations and outcomes of atherosclerotic disease differ between ethnic groups. In addition, the prevalence of risk factors is substantially different. Primary prevention programs are based on data derived from almost exclusively White people. We investigated how race/ethnic differences modify the associations of established risk factors with atherosclerosis and cardiovascular events. Methods: We used data from an ongoing individual participant meta-analysis involving 17 population-based cohorts worldwide. We selected 60,211 participants without cardiovascular disease at baseline with available data on ethnicity (White, Black, Asian or Hispanic). We generated a multivariable linear regression model containing risk factors and ethnicity predicting mean common carotid intima-media thickness (CIMT) and a multivariable Cox regression model predicting myocardial infarction or stroke. For each risk factor we assessed how the association with the preclinical and clinical measures of cardiovascular atherosclerotic disease was affected by ethnicity. Results: Ethnicity appeared to significantly modify the associations between risk factors and CIMT and cardiovascular events. The association between age and CIMT was weaker in Blacks and Hispanics. Systolic blood pressure associated more strongly with CIMT in Asians. HDL cholesterol and smoking associated less with CIMT in Blacks. Furthermore, the association of age and total cholesterol levels with the occurrence of cardiovascular events differed between Blacks and Whites. Conclusion: The magnitude of associations between risk factors and the presence of atherosclerotic disease differs between race/ethnic groups. These subtle, yet significant differences provide insight in the etiology of cardiovascular disease among race/ethnic groups. These insights aid the race/ethnic-specific implementation of primary prevention
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