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

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

La Casa delle Arti e delle Culture: un ponte tra passato e presente. Massa

Questo lavoro affronta la tematica del vivere la città proiettando il tema dell’abitare per antonomasia dal livello architettonico al livello urbano, elevando il progetto di una casa a quello di una parte di città, proponendosi di ricreare l’identità urbana dei cittadini facendoli sentire parte della stessa comunità, coinquilini della stessa città. Esso si pone come ponte ideale tra il passato e il presente posizionandosi su un sito storico che oggi si presenta degradato mentre in passato rappresentava il fulcro culturale della vita cittadina. La Casa diventa la strada che ricuce la smagliatura tra la “Massa Vecchia” e la “Massa Nova”, due realtà urbanisticamente vicine ma oggi socialmente distanti, il progetto si allarga a “Ponte Urbano” riducendo questa distanza e trasformandosi in un percorso che invita ad “attraversare” e, allo stesso tempo, ad “abitare”

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

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

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

Characteristics of demand for antibiotics in primary care: an almost ideal demand system approach

We model demand for different classes of antibiotics used for respiratory infections in outpatient care using a linear approximate almost ideal demand system approach. We compute elasticities to socioeconomic determinants of consumption and own- and cross- price elasticities between different groups of antibiotics. We find significant elasticities between newer/more expensive generations and older/less expensive generations of antibiotics. The larger use of more expensive antibiotics is also associated with the self-dispensing status of practices, ceteris paribus.Antibiotic use, Demand equations, Demand elasticities, Almost Ideal Model, Self-dispensing

Private education supply in disadvantaged areas of the City of Buenos Aires and 'low-fee private schooling' : comparisons, contexts, and implications

Recent studies have revealed an increase in the enrollment of students coming from vulnerable social sectors in private primary schools in the City of Buenos Aires. To date, the phenomenon of 'private education for the poor' has been principally studied in Asian and African countries, where the deficit of state educational supply has given rise to a multiplicity of private education undertakings of diverse nature. Using official statistical data, this article explores and describes the structure of private education supply in areas of low socioeconomic status in Buenos Aires and assesses the extent to which the category of low-fee private school (LFPS) contributes to understanding this phenomenon. Our analysis reveals a great heterogeneity in this sector of private education in Buenos Aires with regard to financing structures, monthly fees, and the legal forms in which schools operate. We also find the presence of a significant religious component. We suggest the possibility that private provision has helped to mitigate coverage imbalances at a 'micro-local' level in some of the studied areas. Our comparative approach evidences that the notion of LFPS provides a more normative than descriptive view, limiting the perception of a phenomenon that is actually much broader, multifaceted and dynamic.Estudios recientes han evidenciado un crecimiento de la matriculación de alumnos provenientes de sectores sociales vulnerables en escuelas primarias privadas de la Ciudad de Buenos Aires. El fenómeno de la 'educación privada para pobres' ha sido estudiado especialmente en los países de Asia y África donde el evidente déficit de oferta educativa estatal ha dado lugar al surgimiento de una multiplicidad de experiencias educacionales privadas de variada naturaleza. A partir de información estadística oficial, este artículo propone una exploración del modo en que se estructura la oferta privada en las zonas de bajo nivel socioeconómico de Buenos Aires y evalúa en qué medida la categoría de low-fee private school (LFPS) resulta útil para entender el fenómeno. Advertimos en primer lugar la gran heterogeneidad que presenta este subsector de la educación privada en Buenos Aires en cuanto a sus estructuras de financiamiento, el valor de los aranceles mensuales y las formas jurídicas bajo las que opera. Destacamos además la presencia de un importante componente religioso y sugerimos la posibilidad de que la oferta privada ha contribuido a mitigar desequilibrios de cobertura a nivel 'microlocal' en los ámbitos estudiados. Finalmente, consideramos que un enfoque comparado permite evidenciar que la categoría de LFPS opera un recorte más normativo que descriptivo que obtura la percepción de un fenómeno que es en realidad mucho más amplio, multifacético y dinámico.Estudos recentes têm mostrado um crescimento no número de estudantes provenientes de grupos sociais vulneráveis nas escolas primárias particulares da Cidade de Buenos Aires. O fenômeno da 'educação privada para os pobres' foi especialmente estudado nos países da Ásia e da África, onde o déficit da oferta aparente no ensino público levou ao surgimento de uma multiplicidade de experiências educacionais privadas de vários tipos. A partir de estatísticas oficiais, este artigo propõe uma exploração da prestação do setor privado em áreas de baixo nível socioeconômico de Buenos Aires e avalia até que ponto a categoria de low-fee private school (LFPS) é útil para compreender o fenômeno. Primeiro, notamos a grande heterogeneidade que apresenta este subsector do ensino privado em Buenos Aires nas suas estruturas de financiamento, no valor das mensalidades e nas suas formas legais de agir. Ressalta-se também a presença de um importante componente religioso e sugerem-se a possibilidade de que a oferta privada tem contribuido a mitigar desequilibros mico-locales na cobertura das áreas estudadas. Finalmente, consideramos que uma abordagem comparativa torna evidente que a categoria de LFPS opera um corte mais normativo que descritivo que fechou a percepção de um fenômeno que é, na verdade, muito mais ampla, multifacetada e dinâmica