The derived category of a non generic cubic fourfold containing a plane

We describe an Azumaya algebra on the resolution of singularities of the double cover of a plane ramified along a nodal sextic associated to a non generic cubic fourfold containing a plane. We show that the derived category of such a resolution, twisted by the Azumaya algebra, is equivalent to the Kuznetsov component in the semiorthogonal decomposition of the derived category of the cubic fourfold.Comment: 14 pages, many edits and correction

Fourier-Mukai functors and perfect complexes on dual numbers

We show that every exact fully faithful functor from the category of perfect complexes on the spectrum of dual numbers to the bounded derived category of a noetherian separated scheme is of Fourier-Mukai type. The kernel turns out to be an object of the bounded derived category of coherent complexes on the product of the two schemes. We also study the space of stability conditions on the derived category of the spectrum of dual numbers.Comment: 23 pages, Final version to appear in J. Algebr

On coherent sheaves of small length on the affine plane

We classify coherent modules on $k[x,y]$ of length at most $4$ and supported at the origin. We compare our calculation with the motivic class of the moduli stack parametrizing such modules, extracted from the Feit-Fine formula. We observe that the natural torus action on this stack has finitely many fixed points, corresponding to connected skew Ferrers diagrams

Non Uniform Projections of Surfaces in P3\mathbb{P}^3

Consider the projection of a smooth irreducible surface in $\mathbb{P}^3$ from a point. The uniform position principle implies that the monodromy group of such a projection from a general point in $\mathbb{P}^3$ is the whole symmetric group. We will call such points uniform. Inspired by a result of Pirola and Schlesinger for the case of curves, we prove that the locus of non-uniform points of $\mathbb{P}^3$ is at most finite.Comment: 11 pages, no figures. This paper is a result of the work carried out at PRAGMATIC 2016 Research School. Minor changes and journal references adde

Physician dispensing and antibiotic prescriptions

The regulation on prescribing and dispensing of antibiotics has a double purpose: to enhance access to antibiotic treatment and to reduce the inappropriate use of drugs. Nevertheless, incentives to dispensing physicians may lead to inefficiencies. We sketch a theoretical model of the market for antibiotic treatment and empirically investigate the impact of self-dispensing on the per capita outpatient antibiotic consumption using data from small geographic areas in Switzerland. We find evidence that a greater proportion of dispensing practices is associated with higher levels of antibiotic use. This suggests that health authorities have a margin to adjust economic incentives on dispensing practices in order to reduce antibiotic misuse.Physician dispensing, Antibiotic use

Dispensing practices and antibiotic use

The regulation on prescribing and dispensing of antibiotics has a double purpose: to enhance access to antibiotic treatment and to reduce the inappropriate use of drugs. Nevertheless, incentives to dispensing physicians may lead to inefficiencies. We sketch a theoretical model of the market for antibiotic treatment and empirically investigate the impact of self-dispensing on the per capita outpatient antibiotic consumption using data from small geographic areas in Switzerland. We find evidence that a greater proportion of dispensing practices is associated with higher levels of antibiotic use. This suggests that health authorities have a margin to adjust economic incentives on dispensing practices in order to reduce antibiotic misuse.Dispensing, Antibiotic use

Small area variations and welfare loss in the use of antibiotics in the community

This paper seeks to explain local variations in the use of antibiotics in the community and to assess the welfare loss due to heterogeneous attitudes towards the risk of bacterial infections and resistance. Significant differences are observed in the per capita antibiotic consumption measured in defined daily doses per 1000 inhabitants (DID) across small geographic areas in Switzerland. A model is proposed in which antibiotic use varies according to the socioeconomic characteristics of the population, the incidence of infections, antibiotic price and local supply of health care. Quarterly wholesales data on outpatient antibiotics in 2002 were obtained from IHA-IMS Market Research and combined with WHO standardized doses to obtain DID. The paper finds that the most important determinants of variations in outpatient antibiotics use in the community are income, demographic structure of the population and local supply and price of antibiotic treatment. We estimated that unexplained variations may account for 11% of the total antibiotic spending in the community, thus leading to a €6ml loss per year.antibiotic use, small area variations, welfare loss