483 research outputs found
Super-spreading Events and Contribution to Transmission of MERS, SARS, and COVID-19
There is no clear definition for the term ‘super-spreader’ or ‘super-spreading event’. The World Health Organization refers to a super-spreader as a patient (or an event) that may transmit infection to a larger number of individuals than is usual by one individual (or event). In the severe acute respiratory syndrome (SARS) situation, a super-spreading event was defined as the transmission of SARS to at ≥8 contacts, and other authors defined this as individuals infecting an unusually large number of secondary cases [ 1 , 2 ]. A super-spreading event could merely be defined as an event in which one patient infects far more people than an average patient does, which is estimated by the basic reproduction number (R0)
Emergence of COVID-19 (formerly 2019-novel Coronavirus): a new threat from China
Coronaviruses cause diseases in birds, mammals, and humans, and were first identified in the mid-1960s (Lee, 2015; Bande et al., 2015; CDC, 2020). These viruses are named for the crown-like spikes on their surface (CDC, 2020). Based on the classification of the International Committee for Taxonomy of Viruses (ICTV) coronaviruses are from order Nidovirales, family Coronaviridae and subfamily Coronavirinae. The viruses contain a positive sense, single-stranded Ribonucleic acid (RNA) genome ranged from 26 to 32 kilobases (kb) in length and thus have the largest genomes for RNA viruses (van Regenmortel et al., 2000). These viruses are further divided into four main subgroups named alpha, beta, gamma, and delta. There are seven human coronaviruses cause infection in humans including 229E (alpha coronavirus), NL63 (alpha coronavirus), OC43 (beta coronavirus), HKU1 (beta coronavirus), Middle East Respiratory Syndrome, or MERS (beta coronavirus), Severe Acute Respiratory Syndrome, or SARS (beta coronavirus), and the newly identified 2019 Novel Coronavirus (2019-nCoV) (CDC, 2020). Common symptoms of the disease include fever, cough, respiratory symptoms, shortness of breath and breathing difficulties (WHO, 2020)
Optimizing Scan Homogeneity for Building Full-3D Lidars based on Rotating a Multi-Beam Velodyne Rangefinder
Multi-beam lidar (MBL) scanners are compact, light, and accessible 3D sensors with high data rates, but they offer limited vertical resolution and field of view (FOV).
Some recent robotics research has profited from the addition of a degree-of-freedom (DOF) to an MBL to build rotating multi-beam lidars (RMBL) that can achieve high-resolution scans with full spherical FOV. In a previous work, we offered a methodology to analyze the complex 3D scan measurement distributions produced by RMBLs with a rolling DOF and no pitching. In this paper, we investigate the effect of introducing constant pitch angles in the construction of the RMBLs with the purpose of finding a kinematic configuration that optimizes scan homogeneity with a spherical FOV. To this end, we propose a scalar index of 3D sensor homogeneity that is based on the spherical formulation of Ripley's K function. The optimization is performed for the widely used Puck (VLP-16) and HDL-32 sensors by Velodyne.This work was partially funded by the Spanish project {DPI2015-65186-R}. The publication has received support from Universidad de Málaga, Campus de Excelencia AndalucÃa Tech
COVID-19 and the Epidemiological, Diagnostic, Clinical and Therapeutical Challenges of the Cocirculation and Coinfection with Tropical Pathogens
Before the beginning of the pandemic of the Coronavirus Disease 2019 (COVID-19), caused, by the infection due to the Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2), there was already concern in many regions of the world, as occurred in Latin America but certainly also in Africa and Asia, regarding the epidemiology of communicable diseases in these areas, including tropical diseases [1-4].
As usually occurs in other epidemics, during the pandemic there is high suspicion on COVID-19 diagnosis, especially when presenting with classical associated symptoms; many of them, as happens with fever, that may overlap with many other infectious and tropical diseases, including dengue, malaria, leptospirosis, acute Chagas disease, salmonellosis, among many other [5-8]
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