One of the strategies used in some countries to contain the COVID-19 epidemic has been the test-and-isolate policy, generally coupled with contact tracing. Such strategies have been examined in several simulation models, but a theoretical analysis of their effectiveness in simple epidemic model is, to our knowledge, missing. In this paper, we present four epidemic models of either SIR or SEIR type, in which it is assumed that at fixed times the whole population (or a part of the population) is tested and, if positive, isolated.
View Article and Find Full Text PDFThe Carbon Ore Resources Database (CORD) is a working collection of 399 data files associated with carbon ore resources in the United States. The collection includes spatial/non-spatial, filtered, processed, and secondary data files with original data acquisition efforts focused on domestic coal resources. All data were acquired via open-source, online sources from a combination of 18 national, state, and university entities.
View Article and Find Full Text PDFMalignant vascular tumors are exceedingly rare in childhood. Generally, their prognosis is dependent from a microscopically complete surgical resection. We observed the case of a 4-year-old boy affected by malignant endovascular papillary angioendothelioma, a rare vascular tumor of intermediate malignancy, involving all his left leg and partially the pelvis.
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