Search results for "Morphisms"
showing 10 items of 190 documents
Homomorphisms and composition operators on algebras of analytic functions of bounded type
2005
Abstract Let U and V be convex and balanced open subsets of the Banach spaces X and Y, respectively. In this paper we study the following question: given two Frechet algebras of holomorphic functions of bounded type on U and V, respectively, that are algebra isomorphic, can we deduce that X and Y (or X * and Y * ) are isomorphic? We prove that if X * or Y * has the approximation property and H wu ( U ) and H wu ( V ) are topologically algebra isomorphic, then X * and Y * are isomorphic (the converse being true when U and V are the whole space). We get analogous results for H b ( U ) and H b ( V ) , giving conditions under which an algebra isomorphism between H b ( X ) and H b ( Y ) is equiv…
Hurwitz spaces of Galois coverings of P1, whose Galois groups are Weyl groups
2006
Abstract We prove the irreducibility of the Hurwitz spaces which parametrize equivalence classes of Galois coverings of P 1 , whose Galois group is an arbitrary Weyl group, and the local monodromies are reflections. This generalizes a classical theorem due to Luroth, Clebsch and Hurwitz.
Symplectic automorphisms of prime order on K3 surfaces
2006
The aim of this paper is to study algebraic K3 surfaces (defined over the complex number field) with a symplectic automorphism of prime order. In particular we consider the action of the automorphism on the second cohomology with integer coefficients. We determine the invariant sublattice and its perpendicular complement, and show that the latter coincides with the Coxeter-Todd lattice in the case of automorphism of order three. We also compute many explicit examples, with particular attention to elliptic fibrations.
Topological classification of gradient-like diffeomorphisms on 3-manifolds
2004
Abstract We give a complete invariant, called global scheme , of topological conjugacy classes of gradient-like diffeomorphisms, on compact 3-manifolds. Conversely, we can realize any abstract global scheme by such a diffeomorphism.
Circular sturmian words and Hopcroft’s algorithm
2009
AbstractIn order to analyze some extremal cases of Hopcroft’s algorithm, we investigate the relationships between the combinatorial properties of a circular sturmian word (x) and the run of the algorithm on the cyclic automaton Ax associated to (x). The combinatorial properties of words taken into account make use of sturmian morphisms and give rise to the notion of reduction tree of a circular sturmian word. We prove that the shape of this tree uniquely characterizes the word itself. The properties of the run of Hopcroft’s algorithm are expressed in terms of the derivation tree of the automaton, which is a tree that represents the refinement process that, in the execution of Hopcroft’s alg…
Conjugate unstable manifolds and their underlying geometrized Markov partitions
2000
Abstract Conjugate unstable manifolds of saturated hyperbolic sets of Smale diffeomorphisms are characterized in terms of the combinatorics of their geometrized Markov partitions. As a consequence, the relationship between the local and the global point of view is also made explicit.
A note on endomorphisms of hypercentral groups
2002
Abstract Let H be a subnormal subgroup of a hypercentral group G. We prove that endomorphisms of G are uniquely determined by their restrictions to H if and only if Hom(G/HG,G)=0, and draw some consequences from this fact.
FOKI AND BSMI VITAMIN D RECEPTOR GENE POLYMORPHISMS, ARE THEY ASSOCIATED WITH INTIMA MEDIA THICKNESS IN ESSENTIAL HYPERTENSIVE INDIVIDUALS
2015
Objective: Analyzing 25hydroxyvitaminD (25[OH]D) serum levels and common carotid intimamedia thickness (IMT) relationship, and evaluating the association of FokI and BsmI vitamin D receptor (VDR) gene polymorphisms with IMT in essential hypertensive patients were our study aims. Design and method: We enrolled seventyone essential hypertensive patients, 18–75 years old. Patients underwent clinical blood pressure (BP) measurement, 24 hour ambulatory blood pressure monitoring, routine blood test, 25[OH]D assay and common carotid IMT evaluation. FokI and BsmIVDRpolymorphisms were analyzed by polymerase chain reactionrestriction fragment length polymorphism (PCRRFLP).
Logarithmic Equal-Letter Runs for BWT of Purely Morphic Words
2022
In this paper we study the number r(bwt) of equal-letter runs produced by the Burrows-Wheeler transform (BWT) when it is applied to purely morphic finite words, which are words generated by iterating prolongable morphisms. Such a parameter r(bwt) is very significant since it provides a measure of the performances of the BWT, in terms of both compressibility and indexing. In particular, we prove that, when BWT is applied to whichever purely morphic finite word on a binary alphabet, r(bwt) is O(log n), where n is the length of the word. Moreover, we prove that r(bwt) is Theta(log n) for the binary words generated by a large class of prolongable binary morphisms. These bounds are proved by pro…
Candidate Gene and Genome-Wide Association Studies for Circulating Leptin Levels Reveal Population and Sex-Specific Associations in High Cardiovascul…
2019
Leptin is a hormone crucial in the regulation of food intake and body-weight maintenance. However, the genes and gene variants that influence its plasma levels are still not well known. Results of studies investigating polymorphisms in candidate genes have been inconsistent, and, in addition, very few genome-wide association studies (GWAS) have been undertaken. Our aim was to investigate the genes and gene variants most associated with plasma leptin concentrations in a high-cardiovascular-risk Mediterranean population. We measured plasma leptin in 1011 men and women, and analyzed the genetic factors associated using three approaches: (1) Analyzing the single nucleotide polymorphisms (SNPs) …