On characters of Chevalley groups vanishing at the non-semisimple elements

Let G be a finite simple group of Lie type. In this paper we study characters of G that vanish at the non-semisimple elements and whose degree is equal to the order of a maximal unipotent subgroup of G. Such characters can be viewed as a natural generalization of the Steinberg character. For groups G of small rank we also determine the characters of this degree vanishing only at the non-identity unipotent elements.Comment: Dedicated to Lino Di Martino on the occasion of his 65th birthda

Introduction : testing freedom

PostprintPeer reviewe

Almost cyclic elements in cross-characteristic representations of finite groups of Lie type

This paper is a significant contribution to a general programme aimed to classify all projective irreducible representations of finite simple groups over an algebraically closed field, in which the image of at least one element is represented by an almost cyclic matrix (that is, a square matrix $M$ of size $n$ over a field $F$ with the property that there exists $\alpha\in F$ such that $M$ is similar to $diag(\alpha \cdot Id_k, M_1)$, where $M_1$ is cyclic and $0\leq k\leq n$). While a previous paper dealt with the Weil representations of finite classical groups, which play a key role in the general picture, the present paper provides a conclusive answer for all cross-characteristic projective irreducible representations of the finite quasi-simple groups of Lie type and their automorphism groups.Comment: To appear on Journal of Group Theor

Characterization of different Arundo donax L. Clones from the Mediterranean region

The present study assessed the behaviour of a tour ecotypes of Arundo donax L. (giant reed) as a perennial rhizomatous grass with an increasing interest due to its high biomass production and great s adaptability to stress conditions. In this study we perform a molecular, physiological and biomass characterization in greenhouse conditions on four mediterranean ecotypes. Not large significant differences were found in physiological and biomass parameters. However, it was possible to observe large differences in the chromosome count for the four ecotypes. In this way, we detected different number of chromosomes for each ecotype (98 to 122), but surprisingly, no correlation was observad between their chromosomes number and their physiological and biomass responses

On differential equations associated with perturbations of orthogonal polynomials on the unit circle

In this contribution, we propose an algorithm to compute holonomic second-order differential equations satisfied by some families of orthogonal polynomials. Such algorithm is based in three properties that orthogonal polynomials satisfy: a recurrence relation, a structure formula, and a connection formula. This approach is used to obtain second-order differential equations whose solutions are orthogonal polynomials associated with some spectral transformations of a measure on the unit circle, as well as orthogonal polynomials associated with coherent pairs of measures on the unit circle.Comunidad de MadridUniversidad de Alcal

Validação de um método para detecção e quantificação de soja culticance tolerante a herbicidas imidazolinonas por PCR convencional e quantitativo.

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Comportamento meiótico e viabilidade de pólen de bananeiras autotetraploides NBA-14.

A indução da duplicação de cromossomos é uma alternativa para gerar novos triploides de bananeira resistentes a doenças e com frutos de qualidade. Os autotetraploides obtidos através desta técnica poderão ser utilizados para gerar triploides secundários (AAA) mediante o cruzamento com diploides (AA)