On the homogeneous ideal of unreduced projective schemes.
On the Kodaira dimension of the moduli space of curves, II. The even-genus case.
On the k-regularity of some proyective manifolds.
The conjecture on the (degree-codimension + 1) - regularity of projective varieties is proved for smooth linearly normal polarized varieties (X,L) with L very ample, for low values of Delta(X,L) = degree-codimension-1. Results concerning the projective normality of some classes of special varieties including scrolls over curves of genus 2 and quadric fibrations over elliptic curves, are proved.
On the Lüroth Semigroup of curves lying on a smooth quadric.
On the nonemptiness of the adjoint linear system of a hyperplane section of a threefold.
On the nonemptiness of the adjoint linear system of a hyperplane section of a threefold.
On the number of compatibly Frobenius split subvarieties, prime -ideals, and log canonical centers
Let be a projective Frobenius split variety with a fixed Frobenius splitting . In this paper we give a sharp uniform bound on the number of subvarieties of which are compatibly Frobenius split with . Similarly, we give a bound on the number of prime -ideals of an -finite -pure local ring. Finally, we also give a bound on the number of log canonical centers of a log canonical pair. This final variant extends a special case of a result of Helmke.
On the pole placement problem for linear systems of arbitrary genus.
On the preservation of k-very ampleness under adjunction.
On the projective normality of complete linear series on an algebraic curve.
On the relative adjunction mapping.
On the second sectional geometric genus of quasi-polarized manifolds.
On the third adjoint contractions.
On the variety of linear series on a singular curve
Let be an integral projective curve with . For all positive integers , let be the set of all with and spanned. Here we prove that if , then except in a few cases (essentially if is a double covering).
On the variety of quadrics of rank four containing a projective curve
Sia una curva proeittiva e lissa, generali nel senso di Brill-Noether, indichiamo con l'insieme algebrico di quadrici di rango contenendo a . In questo lavoro noi descriviamo birazionalmente i componenti irriducibile di .
On the variety of special linear systems on an algebraic curve.
On threefolds admitting a bielliptic curve as abstract complete intersection.
Optimal bound for the number of -curves on extremal rational surfaces.
Osculatory behavior and second dual varieties of Del Pezzo surfaces.