Results 21 to 30 of about 13,112 (262)
Matrix positivity preservers in fixed dimension. I [PDF]
, 2016 A classical theorem proved in 1942 by I.J. Schoenberg describes all real-valued functions that preserve positivity when applied entrywise to positive semidefinite matrices of arbitrary size; such functions are necessarily analytic with non-negative ...
Belton, Alexander +3 more
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Immanant Conversion on Symmetric Matrices
Special Matrices, 2014 Letr Σn(C) denote the space of all n χ n symmetric matrices over the complex field C. The main objective of this paper is to prove that the maps Φ : Σn(C) -> Σn (C) satisfying for any fixed irre- ducible characters X, X' -SC the condition dx(A +aB) = dχ·(
Purificação Coelho M. +2 more
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Hyperbolicity preservers and majorization [PDF]
, 2010 The majorization order on $\RR^n$ induces a natural partial ordering on the space of univariate hyperbolic polynomials of degree $n$. We characterize all linear operators on polynomials that preserve majorization, and show that it is sufficient (modulo ...
Borcea +12 more
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On multiplicative (strong) linear preservers of majorizations [PDF]
Sahand Communications in Mathematical Analysis, 2016 In this paper, we study some kinds of majorizations on $textbf{M}_{n}$ and their linear or strong linear preservers. Also, we find the structure of linear or strong linear preservers which are multiplicative, i.e.
Mohammad Ali Hadian Nadoshan +1 more
doaj
Plant-Derivatives Small Molecules with Antibacterial Activity
Antibiotics, 2021 The vegetal world constitutes the main factory of chemical products, in particular secondary metabolites like phenols, phenolic acids, terpenoids, and alkaloids.
Sana Alibi, Dámaso Crespo, Jesús Navas
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Substrate Words Examined from the Perspective of Linguistic Geography (III) [PDF]
Philologia, 2023 In this article we have proposed to present results of the research of the layer of autochthonous words from the Romanian language, namely the letter C (căciulă – ciucă).
Ecaterina PLEŞCA
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Maps on classes of Hilbert space operators preserving measure of commutativity [PDF]
, 2014 In this paper first we give a partial answer to a question of L. Moln\'ar and W. Timmermann. Namely, we will describe those linear (not necessarily bijective) transformations on the set of self-adjoint matrices which preserve a unitarily invariant norm ...
Gehér, György Pál, Nagy, Gergő
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Full column rank preservers that preserve semipositivity of matrices
Special Matrices, 2018 Left invertibility preservers on Mm,n(ℝ), m ≥ n, that preserve either semipositivity of matrices or the subset of minimally semipositive matrices are studied. We prove that such maps cannot be degenerate.
Arumugasamy Chandrashekaran +1 more
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Mayo Clinic Proceedings, 2011 Of the estimated 1.5 million men and women who were diagnosed as having cancer in 2010, approximately 10% are younger than 45 years. For these individuals, cancer treatment can be lifesaving but can permanently affect reproductive capacity. The American Society of Clinical Oncology has recommended that oncologists discuss the possibility of infertility
Pasquale Patrizio, A. L. Caplan
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Linear transformations of tropical matrices preserving the cyclicity index
Special Matrices, 2021 We combine matrix theory and graph theory methods to give a complete characterization of the surjective linear transformations of tropical matrices that preserve the cyclicity index.
Guterman Alexander +2 more
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