Results 1 to 10 of about 705 (40)
Validation of locomotion scoring as a new and inexpensive technique to record circadian locomotor activity in large mammals [PDF]
Heliyon, 2018 Background: The locomotor activity (LA) rhythm, widely studied in rodents, has not been fully investigated in large mammals. This is due to the high cost and the brittleness of the required devices.
H. Farsi +7 more
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Free Proalgebraic Groups [PDF]
Épijournal de Géométrie Algébrique, 2020 Replacing finite groups by linear algebraic groups, we study an algebraic-geometric counterpart of the theory of free profinite groups. In particular, we introduce free proalgebraic groups and characterize them in terms of embedding problems.
Michael Wibmer
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Galois correspondence theorem for Picard-Vessiot extensions [PDF]
, 2015 In this paper, we generalize the definition of the differential Galois group and the Galois correspondence theorem established previously for Picard-Vessiot extensions of real differential fields with real closed field of constants to any Picard-Vessiot ...
Crespo, Teresa +2 more
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A partial factorization of the powersum formula
International Journal of Mathematics and Mathematical Sciences, Volume 2004, Issue 58, Page 3075-3101, 2004., 2004 For any univariate polynomial P whose coefficients lie in an ordinary differential field 𝔽 of characteristic zero, and for any constant indeterminate α, there exists a nonunique nonzero linear ordinary differential operator ℜ of finite order such that the αth power of each root of P is a solution of ℜzα = 0, and the coefficient functions of ℜ all lie ...
John Michael Nahay
wiley +1 more source
Galoisian and qualitative approaches to linear Polyanin-Zaitsev vector fields
Open Mathematics, 2018 In this paper we study a particular parametric family of differential equations, the so-called Linear Polyanin-Zaitsev Vector Field, which has been introduced in a general case in [1] as a correction of a family presented in [2].
Acosta-Humánez Primitivo B. +2 more
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Differential resolvents of minimal order and weight
International Journal of Mathematics and Mathematical Sciences, Volume 2004, Issue 54, Page 2867-2893, 2004., 2004 We will determine the number of powers of α that appear with nonzero coefficient in an α‐power linear differential resolvent of smallest possible order of a univariate polynomial P(t) whose coefficients lie in an ordinary differential field and whose distinct roots are differentially independent over constants.
John Michael Nahay
wiley +1 more source
Powersum formula for polynomials whose distinct roots are differentially independent over constants
International Journal of Mathematics and Mathematical Sciences, Volume 32, Issue 12, Page 721-738, 2002., 2002 We prove that the author′s powersum formula yields a nonzero expression for a particular linear ordinary differential equation, called a resolvent, associated with a univariate polynomial whose coefficients lie in a differential field of characteristic zero provided the distinct roots of the polynomial are differentially independent over constants.
John Michael Nahay
wiley +1 more source
Multivariable dimension polynomials and new invariants of differential field extensions
International Journal of Mathematics and Mathematical Sciences, Volume 27, Issue 4, Page 201-214, 2001., 2001 We introduce a special type of reduction in the ring of differential polynomials and develop the appropriate technique of characteristic sets that allows to generalize the classical Kolchin′s theorem on differential dimension polynomial and find new differential birational invariants of a finitely generated differential field extension.
Alexander B. Levin
wiley +1 more source
Differential Invariants of Conformal and Projective Surfaces [PDF]
, 2007 We show that, for both the conformal and projective groups, all the differential invariants of a generic surface in three-dimensional space can be written as combinations of the invariant derivatives of a single differential invariant. The proof is based
Hubert, Evelyne, Olver, Peter J.
core +8 more sources
Algebraic and qualitative remarks about the family yy′ = (αxm+k–1 + βxm–k–1)y + γx2m–2k–1
Open Mathematics, 2019 The aim of this paper is the analysis, from algebraic point of view and singularities studies, of the 5-parametric family of differential ...
Rodríguez-Contreras Jorge +2 more
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