We show several examples of integrable systems related to special K3 and rational surfaces (e.g., an elliptic K3 surface, a K3 surface given by a double covering of the projective plane, a rational elliptic surface, etc.). The construction, based on Beauvilles’s general idea, is considerably simplified by the fact that all examples are described by hyperelliptic curves and Jacobians. This also ...

We characterized a persistently Junín virus (JUNV)-infected BHK-21 cell line obtained by experimental infection with the XJCl3 strain. This cell line, named K3, produced low levels of virus in supernatants which were not influenced by the presence of defective interfering (DI) particles after the first year of infection. K3 cells were able to exclude superinfection of the homologous JUNV and th...

The Picard group of S is generated by two effective divisors C and F with C = −2, F 2 = 0 and C · F = 1. It can be realized as an elliptic fiberation over P with a unique section C, fibers F and λ = 2. It is the same special K3 surface used by Bryan and Leung in their counting of curves on K3 surfaces [B-L]. It is actually the attempt to understand their method that leads us to our proof. We wi...

The aim of this study was to investigate the effect of 50% hydrofluoric acid (HF) surface treatment on the cyclic fatigue resistance (CFR) of K3 NiTi instruments. Twenty as-received and twenty HF-treated K3 NiTi instruments were compared in CFR. The surface texture and fracture surface of two instrument groups were examined with a scanning electron microscope (SEM). Additionally, any change of ...

In this draft, we study the deformation of a proper smooth curve in positive characteristics within the moduli of K3. We expect that the curve can be lifted to the Witt ring with generic fiber a Shimura curve. Given an algebraic closed field k, a double-point K3 surface over k is a projective surface with at worst rational double point singularities whose minimal resolution is a (smooth) K3 sur...

We study the maps induced on cohomology by a Nikulin (i.e. a symplectic) involution on a K3 surface. We parametrize the eleven dimensional irreducible components of the moduli space of algebraic K3 surfaces with a Nikulin involution and we give examples of the general K3 surface in various components. We conclude with some remarks on MorrisonNikulin involutions, these are Nikulin involutions wh...

INTRODUCTION The purpose of this study was to evaluate the effect of various degrees of cyclic fatigue on torsional failure and torsional preloading on the cyclic fatigue life of heat-treated K3XF nickel-titanium (NiTi) instruments (SybronEndo, Orange, CA). METHODS The mean number of cycles until failure (Nf) of K3XF and K3 NiTi instruments was examined in a 3-point bending apparatus with a 7...