322,929 research outputs found
A footnote to a theorem of Kawamata
No full textKawamata has shown that the quasi-Albanese map of a quasi-projective variety
with log-irregularity equal to the dimension and log-Kodaira dimension 0 is
birational. In this note we show that under these hypotheses the quasi-Albanese
map is proper in codimension 1 as conjectured by Iitaka.Comment: Added an addendum by O. Fujino, M. Mendes Lopes, R. Pardini and S.
Tirabassi that contains an alternative proof of Theorem A in the paper and
explains how to avoid an unsubstantiated claim made in the original proo
On the Brauer group of bielliptic surfaces
No full textWe provide explicit generators for the torsion of the second cohomology of
bielliptic surfaces, and we use this to study pullback map between Brauer group
of a bielliptic surface and that of its canonical cover.Comment: Main Article by E. Ferrari, S. Tirabassi and M. Vodrup. Appendix by
J. Bergstr\"om and S. Tirabassi. Comments are welcome.V2: fixed a minor
mistake in the proof of lemma 4.1, improved introduction, added example
Derived equivalences of canonical covers of hyperelliptic and Enriques surfaces in positive characteristic
No full textWe prove that any Fourier–Mukai partner of an abelian surface over an algebraically closed field of positive characteristic is isomorphic to a moduli space of Gieseker-stable sheaves. We apply this fact to show that the set of Fourier–Mukai partners of a canonical cover of a hyperelliptic or Enriques surface over an algebraically closed field of characteristic greater than three is trivial. These results extend earlier results of Bridgeland–Maciocia and Sosna to positive characteristic
GV-subschemes and their embeddings in principally polarized abelian varieties
No full textWe prove that any embedding of a GV-subscheme in a principally polarized abelian variety does not factor through any nontrivial isogeny. As an application, we present a new proof of a theorem of Clemens-Griffiths identifying the intermediate Jacobian of a smooth cubic threefold to the Albanese variety of its Fano surface of lines
Effective characterization of quasi-abelian surfaces
No full textLet V be a smooth quasi-projective complex surface such that the first three logarithmic plurigenera 1 (), 2 ()and 3 () are equal to 1 and the logarithmic irregularity () is equal to 2. We prove that the quasi-Albanesemorphism : → () is birational and there exists a finite set S such that is proper over () \ , thusgiving a sharp effective version of a classical result of Iitaka [12].Unknown properties of abstract geometric object
Influence of CAG repeat polymorphism on the targets of testosterone action
No full textIn the last decade, ample evidence has demonstrated the growing importance of androgen receptor (AR) CAG repeat polymorphism in andrology. This genetic parameter is able to condition the peripheral effects of testosterone and therefore to influence male sexual function and fertility, cardiovascular risk, body composition, bone metabolism, the risk of prostate and testicular cancer, the psychiatric status, and the onset of neurodegenerative disorders. In this review, we extensively discuss the literature data and identify a role for AR CAG repeat polymorphism in conditioning the systemic testosterone effects. In particular, our main purpose was to provide an updated text able to shed light on the many and often contradictory findings reporting an influence of CAG repeat polymorphism on the targets of testosterone action. © 2015 Giacomo Tirabassi et al
Evoluzione geomorfologica della bassa pianura mantovana e reggiana (Pianura Padana, Italia Settentrionale)
No full textIl lavoro si occupa dell’evoluzione geomorfologica del settore di Pianura Padana che comprende la parte sud-occidentale della Provincia di Mantova e l'estremità settentrionale della Provincia di Reggio nell'Emilia, separate tra loro dal F. Po nel tratto tra foce Enza e foce Oglio.Lo studio geomorfologico è stato realizzato attraverso la ricerca bibliografica, il rilevamento sul terreno, lo studio delle fotografie aeree (sia analogiche sia digitali) e l’utilizzo di Sistemi Informativi Territoriali.Sono stati realizzati una Carta del microrilievo, un Modello Digitale delle Altezze e una una Carta geomorfologica
Una grande struttura “Fiorano” esplorata a Bazzarola (Reggio Emilia)
No full textLo scavo archeologico di Bazzarola (RE), il suo studio multidisciplinar
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