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The Descartes Rule of Signs, which establishes a bound on the number of positive roots of a polynomial with real coefficients, is extended to polynomials with complex coefficients. The extension is modified to bound the number of complex roots in a given direction on the complex plane, giving rise to the Descartes Signature of a polynomial. The search for the roots of a polynomial is sometimes ...
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n t odern healthcare operates under the banner of “evidencebased” medicine. The pursuit of such evidence, however, is ot exclusively driven by need, but by the vailability of funds, which in turn deends partly on the likelihood of profit. ore portentously, the pursuit of data is ounded by the prevailing conceptions of iological plausibility. This essay makes he case that such borders are not re...
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ژورنال
عنوان ژورنال: Nature
سال: 2012
ISSN: 0028-0836,1476-4687
DOI: 10.1038/483540a