Results for "Valentina Apollonio"

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Criticality of measures on 2-d Ising configurations: from square to hexagonal graphsJun 06 2019On the space of Ising configurations on the 2-d square lattice, we consider a family of non Gibbsian measures introduced by using a pair Hamiltonian, depending on an additional inertial parameter $q$. These measures are related to the usual Gibbs measure ... More
Shaken dynamics for the 2d ising modelApr 12 2019We define a Markovian parallel dynamics for a class of nearest neighbors spin systems. In the dynamics, beside the two usual parameters $J$, the strength of the interaction, and $\lambda$, the external field, it appears an inertial parameter $q$, measuring ... More
A minimal partition problem with trace constraint in the Grushin planeJul 14 2016We study a variational problem for the perimeter associated with the Grushin plane, called minimal partition problem with trace constraint. This consists in studying how to enclose three prescribed areas in the Grushin plane, using the least amount of ... More
Divided difference operators on polytopesJul 27 2013We define convex-geometric counterparts of divided difference (or Demazure) operators from the Schubert calculus and representation theory. These operators are used to construct inductively polytopes that capture Demazure characters of representations ... More
On intersection indices of subvarieties in reductive groupsMay 27 2006I will present an explicit formula for the intersection indices of the Chern classes of an arbitrary reductive group with hypersurfaces. This formula has the following applications. First, it allows to compute explicitly the Euler characteristic of complete ... More
Fusion systems containing pearlsOct 19 2017Feb 16 2018An $\mathcal{F}$-essential subgroup is called a pearl if it is either elementary abelian of order $p^2$ or non-abelian of order $p^3$. In this paper we start the investigation of fusion systems containing pearls: we determine a bound for the order of ... More
Beta sheet propensity and the genetic codeNov 09 2014So far mutations analysis was performed in terms of transitions and trasversions, so on the basis of the molecule, or in terms of GC-content and isochors, through the quantification of GC->AT mutations over AT->GC mutations. We tried a different approach ... More
G-quadruplexes and mRNA localizationOct 01 2013G-quadruplexes represent a novelty for molecular biology. Their role inside the cell remains mysterious. We investigate a possible correlation with mRNA localization. In particular, we hypothesize that Gquadruplexes influence fluid dynamics.
Newton-Okounkov polytopes of flag varieties for classical groupsFeb 07 2019For classical groups SL(n), SO(n) and Sp(2n), we define uniformly geometric valuations on the corresponding complete flag varieties. The valuation in every type comes from a natural coordinate system on the open Schubert cell and is combinatorially related ... More
DNA evolved to minimize frameshift mutationsSep 03 2013Point mutations can surely be dangerous but what is worst than to lose the reading frame?! Does DNA evolved a strategy to try to limit frameshift mutations?! Here we investigate if DNA sequences effectively evolved a system to minimize frameshift mutations ... More
The role of Junk DNAOct 20 2014Oct 27 2014Many efforts have been done in order to explain the role of junk DNA, but its function remain to be elucidated. In addition the GC-content variations among species still represent an enigma. Both these two misteries can have a common explanation: we hypothesize ... More
Complex structures of dense lithium: electronic originMar 12 2016Lithium - the lightest alkali metal - exhibits unexpected structures and electronic behaviour at high pressures. As the heavier alkalis, Li is bcc at ambient pressure and transforms first to fcc (at 7.5 GPa). The post-fcc high-pressure form Li-cI16 (at ... More
On the coarse geometry of the complex of domainsMay 05 2011The complex of domains $D(S)$ is a geometric tool with a very rich simplicial structure, it contains the curve complex $C(S)$ as a simplicial subcomplex. In this paper we shall regard it as a metric space, endowed with the metric which makes each simplex ... More
Multiplicity and Underlying Event in ALICE: as measurements and as tools to probe QCDMay 15 2018With the high collision energies at the LHC, the contributions to particle production from hard-QCD processes increase, but it remains dominated by soft-QCD processes. Such processes challenge the theoretical models, since they are described by non-perturbative ... More
Deciphering regulation in eukaryotic cell: from sequence to functionSep 23 2014A transversal topic of my research has been the development and application of computational methods for DNA sequence analysis. The methods I have been developing aim at improving our understanding of the regulation processes happening in normal and cancer ... More
Insights Into Quantitative Biology: analysis of cellular adaptationJul 01 2013In the last years many powerful techniques have emerged to measure protein interactions as well as gene expression. Many progresses have been done since the introduction of these techniques but not toward quantitative analysis of data. In this paper we ... More
Newton-Okounkov polytopes of flag varietiesJun 01 2015Mar 03 2016We compute the Newton--Okounkov bodies of line bundles on the complete flag variety of GL_n for a geometric valuation coming from a flag of translated Schubert subvarieties. The Schubert subvarieties correspond to the terminal subwords in the decomposition ... More
Chern classes of reductive groups and an adjunction formulaNov 15 2004Dec 29 2005In this paper, I construct noncompact analogs of the Chern classes of equivariant vector bundles over complex reductive groups. For the tangent bundle, these Chern classes yield an adjunction formula for the Euler characteristic of complete intersections ... More
Gelfand-Zetlin polytopes and flag varietiesJun 26 2009I construct a correspondence between the Schubert cycles on the variety of complete flags in C^n and some faces of the Gelfand-Zetlin polytope associated with the irreducible representation of SL_n(C) with a strictly dominant highest weight. The construction ... More
A Gauss-Bonnet theorem for constructible sheaves on reductive groupsMay 02 2002We prove an analog of the Gauss-Bonnet formula for constructible sheaves on reductive groups. As a corollary from this formula we get that if a perverse sheaf on a reductive group is equivariant under the adjoint action, then its Euler characteristic ... More
On the nilpotency class of finite groups with a Frobenius group of automorphismsJun 14 2018Suppose that a metacyclic Frobenius group $FH$, with kernel $F$ and complement $H$, acts by automorphisms on a finite group $G$, in such a way that $C_G(F)$ is trivial and $C_G(H)$ is nilpotent. It is known that $G$ is nilpotent and its nilpotency class ... More
Just an Update on PMING Distance for Web-based Semantic Similarity in Artificial Intelligence and Data MiningJan 09 2017One of the main problems that emerges in the classic approach to semantics is the difficulty in acquisition and maintenance of ontologies and semantic annotations. On the other hand, the Internet explosion and the massive diffusion of mobile smart devices ... More
New outcomes in mutation rates analysisJul 21 2013The GC-content is very variable in different genome regions and species but although many hypothesis we still do not know the reason why. Here we show that a relationship exists with the mutation rate, in particular we noticed a new recurrence in the ... More
Geometric mitosisSep 22 2014We describe an elementary convex geometric algorithm for realizing Schubert cycles in complete flag varieties by unions of faces of polytopes. For GL_n and Gelfand--Zetlin polytopes, combinatorics of this algorithm coincides with that of the mitosis on ... More
Study of charged-particle multiplicities with ALICEJun 30 2017The multiplicity measurements include the pseudorapidity density, $\rm{d}N_{\rm ch}/\rm{d}{\eta}$, and the probability distribution as a function of the number of charged particles, $\rm{P}(N_{\rm ch})$. ALICE has measured the multiplicities for three ... More
Oscillation Physics with a Neutrino FactoryOct 13 2002A generation of neutrino experiments have established that neutrinos mix and probably have mass. The mixing phenomenon points to processes beyond those of the Standard Model, possibly at the Grand Unification energy scale. A extensive sequence of of experiments ... More
Fluctuations of the total number of critical points of random spherical harmonicsOct 01 2015We determine the asymptotic law for the fluctuations of the total number of critical points of random Gaussian spherical harmonics in the high degree limit. Our results have implications on the sophistication degree of an appropriate percolation process ... More
Joint distribution of the process and its sojourn time for pseudo-processes governed by high-order heat equationJan 23 2010Mar 04 2010Consider the high-order heat-type equation $\partial u/\partial t=\pm \partial^N u/\partial x^N$ for an integer $N>2$ and introduce the related Markov pseudo-process $(X(t))_{t\ge 0}$. In this paper, we study the sojourn time $T(t)$ in the interval $[0,+\infty)$ ... More
Updated constraints from the PLANCK experiment on modified gravityJul 08 2013A modification of the action of the general relativity produces a different pattern for the growth of the cosmic structures below a certain length-scale leaving an imprint on the cosmic microwave background (CMB) anisotropies. We re-examine the upper ... More
Phenomenological tests of the Two-Higgs-Doublet Model with MFV and flavour-blind phasesFeb 08 2011In the context of a Two-Higgs-Doublet Model in which Minimal Flavour Violation (MFV) is imposed, one can allow the presence of flavour-blind CP-violating phases without obtaining electric dipole moments that overcome the experimental bounds. This choice ... More
Prospects for hydrogen storage in grapheneJul 24 2012Hydrogen-based fuel cells are promising solutions for the efficient and clean delivery of electricity. Since hydrogen is an energy carrier, a key step for the development of a reliable hydrogen-based technology requires solving the issue of storage and ... More
Hypergeometric Functions over Finite Fields and their relations to Algebraic CurvesAug 19 2010In this work we present an explicit relation between the number of points on a family of algebraic curves over $\F_{q}$ and sums of values of certain hypergeometric functions over $\F_{q}$. Moreover, we show that these hypergeometric functions can be ... More
Approximate conditional inference for panel logit models allowing for state dependence and unobserved heterogeneityFeb 26 2007We show that a dynamic logit model for binary panel data allowing for state dependence and unobserved heterogeneity may be accurately approximated by a quadratic exponential model, the parameters of which have the same interpretation that they have in ... More
On a Diophantine problem with one prime, two squares of primes and $s$ powers of twoMar 10 2011Oct 12 2011We refine a result of W.P. Li and Wang on the values of the form $ \lambda_1p_1 + \lambda_2p_2^{2} + \lambda_3p_3^{2} + \mu_1 2^{m_1} +...+ \mu_s 2^{m_s}, $ where $p_1,p_2,p_3$ are prime numbers, $m_1,..., m_s$ are positive integers, $\lambda_1,\lambda_2,\lambda_{3}$ ... More
The Stochastic Properties of $\ell^1$-Regularized Spherical Gaussian FieldsSep 13 2013Convex regularization techniques are now widespread tools for solving inverse problems in a variety of different frameworks. In some cases, the functions to be reconstructed are naturally viewed as realizations from random processes; an important question ... More
A Reduction Principle for the Critical Values of Random Spherical HarmonicsJun 01 2018We study here the random fluctuations in the number of critical points with values in an interval $I\subset \mathbb{R}$ for Gaussian spherical eigenfunctions $\left\{f_{\ell }\right\} $, in the high energy regime where $\ell \rightarrow \infty $. We show ... More
Forbidden subgraphs in the norm graphFeb 05 2015We show that the norm graph constructed in [J. Koll\'{a}r, L. R\'{o}nyai and T. Szab\'o, Norm-graphs and bipartite Tur\'{a}n numbers, Combinatorica, 16 (1996) 399--406] with $n$ vertices about $\frac{1}{2}n^{2-1/t}$ edges, which contains no copy of $K_{t,(t-1)!+1}$, ... More
A multirate numerical scheme for large-scale vehicle traffic simulationOct 18 2016Nowadays the city-wide traffic contains hundreds of thousands of vehicles with different scenarios of their behavior. If a microscopic approach is used it leads to solving tremendous systems of ordinary differential equations whose components have a wide ... More
Kinematic structure of the atmosphere and envelope of the post-AGB star HD56126Oct 26 2007We present results of an analysis of the optical spectrum of the post-AGB star HD56126 (IRAS 07134+1005) based on observations made with the echelle spectrographs of the 6-m telescope with spectral resolutions of R=25000 and 60000 at 4012-8790 AA. The ... More
Anomalous dimensions of finite size field strength operators in N=4 SYMOct 01 2007Nov 14 2007In the N=4 super Yang-Mills theory, we consider the higher order anomalous dimensions gamma_L(g) of purely gluonic operators Tr(F^L) where F is a component of the self-dual field strength. We propose compact closed expressions depending parametrically ... More
Incommensurate host-guest structures in compressed elements: Hume-Rothery effects as originOct 25 2015Discovery of the incommensurate structure in the element Ba under pressure 15 years ago was followed by findings of a series of similar structures in other compressed elements. Incommensurately modulated structures of the host-guest type consist of a ... More
Hardy-type inequalities for the Carnot-Carathéodory distance in the Heisenberg groupMar 20 2019In this paper we study various Hardy inequalities in the Heisenberg group $\mathbb H^n$, w.r.t. the Carnot-Carath\'eodory distance $\delta$ from the origin. We firstly show that the optimal constant for the Hardy inequality is strictly smaller than $n^2 ... More
Clausius entropy for arbitrary bifurcate null surfacesMar 13 2013Dec 06 2013Jacobson's thermodynamic derivation of the Einstein equations was originally applied only to local Rindler horizons. But at least some parts of that construction can usefully be extended to give meaningful results for arbitrary bifurcate null surfaces. ... More
Leveraging over intact priors for boosting control and dexterity of prosthetic hands by amputeesAug 26 2016Non-invasive myoelectric prostheses require a long training time to obtain satisfactory control dexterity. These training times could possibly be reduced by leveraging over training efforts by previous subjects. So-called domain adaptation algorithms ... More
A note on Harris Morrison sweeping families of maximal gonalityFeb 04 2013Mar 11 2013Harris and Morrison constructed semistable families f:F \to Y of k-gonal curves of genus g such that for every k the corresponding modular curves give a sweeping family in the k-gonal locus in the moduli space. Their construction depends on the choice ... More
Associated graded rings of one-dimensional analytically irreducible rings IIOct 19 2010Nov 18 2010Lance Bryant noticed in his thesis that there was a flaw in our paper "Associated graded rings of one-dimensional analytically irreducible rings", J. Algebra 304 (2006), 349-358. It can be fixed by adding a condition, called the BF condition. We discuss ... More
The geometry of flip graphs and mapping class groupsNov 16 2014The space of topological decompositions into triangulations of a surface has a natural graph structure where two triangulations share an edge if they are related by a so-called flip. This space is a sort of combinatorial Teichm\"uller space and is quasi-isometric ... More
A non-existence result on symplectic semifield spreadsApr 29 2015May 22 2015We prove that there do not exist non-Desarguesian symplectic semifield spreads of PG$(5,q^2)$, $q\geq 2^{14}$ even, whose associated semifield has center containing $\mathbb{F}_q$, by proving that the only $\mathbb{F}_q$-linear set of rank 6 disjoint ... More
Mean curvature flow with free boundary in embedded cylinders or cones and uniqueness results for minimal hypersurfacesMay 30 2016Sep 15 2016In this paper we study the mean curvature flow of embedded disks with free boundary on an embedded cylinder or generalised cone of revolution, called the support hypersurface. We determine regions of the interior of the support hypersurface such that ... More
Isoperimetric problem in H-type groups and Grushin spacesNov 19 2014We study the isoperimetric problem in H-type groups and Grushin spaces, emphasizing a relation between them. We prove existence, symmetry and regularity properties of isoperimetric sets, under a symmetry assumption that depends on the dimension.
The contribution of INTEGRAL to blazar scienceOct 29 2008We review 6 years of INTEGRAL observations of blazars, from Target-Of-Opportunity (TOO) to normal observations to coordinated campaigns, from the new and unexpected discoveries to the improvements in this research field. We also shortly review what is ... More
Schubert calculus for algebraic cobordismMar 23 2009Jun 04 2010We establish a Schubert calculus for Bott-Samelson resolutions in the algebraic cobordism ring of a complete flag variety G/B.
The slope conjecture for the fourgonal locusSep 17 2012Apr 17 2013Using vector bundles techniques and the Viehweg weak positivity theorem, we give an answer to the Harris - Stankova slope conjecture for a sufficiently general curve in the fourgonal locus of the moduli space of stable curves. We also refine Harris - ... More
The optical spectrum of R Coronae Borealis close to 2003 declineJun 21 2007Two sets of high-resolution spectra of R CrB obtained during the 2003 light decline are described. The first set was obtained on the descending branch of the light curve when V ~12.0 and the second one in the recovery phase with V ~7.5. The usual sharp ... More
High-latitude supergiants: anomalies in the spectrum of LN Hya in 2010Dec 16 2011High-resolution echelle spectra taken with the 6-m telescope in 2003-2011 are used to study features of the optical spectrum and the velocity field in the atmosphere of the semiregular variable LN Hya in detail. The weak symmetric photospheric absorptions ... More
Improved parameters of the hydrogen-deficient binary star KSPerJun 17 2008Using the high resolution spectral observations obtained with the Nasmyth Echelle Spectrograph NES of the 6m telescope we analysed the optical spectrum of the hydrogen-deficient binary star KSPer. The atmospheric parameters derived are: effective temperature ... More
Calibrating the Local and Platoon Dynamics of Car-following Models on the Reconstructed NGSIM DataOct 10 2016The NGSIM trajectory data are used to calibrate two car-following models - the IDM and the FVDM. We used the I80 dataset which has already been reconstructed to eliminate outliers, unphysical data, and internal and platoon inconsistencies contained in ... More
Reconciling Large And Small-Scale Structure In Twin Higgs ModelsNov 17 2016We study an extension of the Twin Higgs model that solves the Hierarchy problem and simultaneously addresses problems of the large- and small-scale structures of the Universe. Besides naturally providing dark matter (DM) candidates as the lightest charged ... More
Microservices, Continuous Architecture, and Technical Debt Interest: An Empirical StudyOct 25 2018Continuous Architecture (CA) is an approach that supports companies in decreasing the time between deliveries. Migration to microservices is one of the most common situations when companies adopt continuous architecting processes [4]. Companies commonly ... More
A Generalization of the Skew-Normal Distribution: The Beta Skew-NormalApr 21 2011The aim of this article is to introduce a new family of distributions, which generalizes the skew normal distribution (SN). This new family, called Beta skew-normal (BSN), arises naturally when we consider the distributions of order statistics of the ... More
Reasoning about multiple aspects in DLs: Semantics and Closure ConstructionJan 18 2018Starting from the observation that rational closure has the undesirable property of being an "all or nothing" mechanism, we here propose a multipreferential semantics, which enriches the preferential semantics underlying rational closure in order to separately ... More
Trasferring $L^p$ eigenfunction bounds from $S^{2n+1}$ to $h^n$Nov 17 2008By using the notion of contraction of Lie groups, we transfer $L^p-L^2$ estimates for joint spectral projectors from the unit complex sphere $\sfera$ in ${{\mathbb{C}}}^{n+1}$ to the reduced Heisenberg group $h^{n}$. In particular, we deduce some estimates ... More
Equivariant Cobordism of Flag Varieties and of Symmetric VarietiesApr 06 2011We obtain an explicit presentation of the equivariant cobordism ring of a complete flag variety. An immediate corollary is a Borel presentation of the ordinary cobordism ring. Another application is an equivariant Schubert calculus in cobordism. We also ... More
A reconstruction of the multipreference closureMay 05 2019The paper describes a preferential approach for dealing with exceptions in KLM preferential logics, based on the rational closure. It is well known that the rational closure does not allow an independent handling of the inheritance of different defeasible ... More
Restriction estimates for the free two step nilpotent group on three generatorsApr 25 2017Let $G$ be the free two step nilpotent Lie group on three generators and let $L$ be a sub-Laplacian on it. We compute the spectral resolution of $L$ and prove that the operators arising from this decomposition enjoy a Tomas-Stein type estimate.
Reciprocity of gauge operators in N=4 SYMMar 26 2008Apr 04 2008A recently discovered generalized Gribov-Lipatov reciprocity holds for the anomalous dimensions of various twist operators in N=4 SYM. Here, we consider a class of scaling psu(2,2|4) operators that reduce at one-loop to twist-3 maximal helicity gluonic ... More
From second grade fluids to the Navier-Stokes equationsJul 22 2016We consider the limit $\alpha\to0$ for a second grade fluid on a bounded domain with Dirichlet boundary conditions. We show convergence towards a solution of the Navier-Stokes equations under two different types of hypothesis on the initial velocity $u_0$. ... More
Polaris B, an optical companion of Polaris (alpha UMi) system: atmospheric parameters, chemical composition, distance and massAug 02 2007We present an analysis of high-resolution spectroscopic observations of Polaris B, the optical companion of the Polaris Ab system. The star has a radial velocity V_r of -16.6km/s to -18.9km/s, and a projected rotational velocity vsini=110 km/s. The derived ... More
Local stability conditions and calibrating procedure for new car-following models used in driving simulatorsOct 17 2016The Intelligent Driver Model is studied and several drawbacks with respect to driving simulators are defined. We present two modifications of the IDM. The first one gives any predefined distance to the leading vehicle in a steady state. The second modification ... More
Patterns of flavour violation at the dawn of the LHC eraOct 19 2012The experimental success of the predictions of the Standard Model in the flavour sector suggests that New Physics should possess a highly non-generic flavour structure. Different approaches to this idea of Minimal Flavour Violation have been proposed ... More
New Physics scenarios in light of new and old flavour dataOct 02 2012The flavour observables currently in the spotlight because of the recent experimental updates or because of the presence of tensions with the Standard Model predictions are reviewed in their main aspects. These quantities suggest the development of a ... More
First implications of LHCb data on models beyond the Standard ModelSep 24 2012We discuss the theoretical and experimental details of two of the main results obtained by LHCb with the 2011 data, namely the measurement of the mixing-induced CP-violation in the decay B_s -> J/psi phi and the upper limits on the decays B_(s) -> mu+ ... More
Electronic structure and Peierls instability in graphene nanoribbons sculpted in graphaneOct 31 2009Graphene nanoribbons are semiconductor nanostructures with great potentials in nanoelectronics. Their realization particularly with small lateral dimensions below a few nanometers, however, remains challenging. Here we theoretically analyze zig-zag graphene ... More
Measurements of charged-particle distributions with the ATLAS detectorOct 19 2016Inclusive charged-particle measurements probe the low-energy region of the non-perturbative quantum chromodynamics. The ATLAS collaboration has recently measured the charged-particle multiplicity and its dependence on transverse momentum and pseudorapidity ... More
Semidirect Products and Wreath Products of LocalitiesMay 09 2019We develop a theory of semidirect products of partial groups and localities. Our concepts generalize the notions of direct products of partial groups and localities, and of semidirect products of groups.
Infinite Shannon entropyDec 21 2012Jan 07 2013Even if a probability distribution is properly normalizable, its associated Shannon (or von Neumann) entropy can easily be infinite. We carefully analyze conditions under which this phenomenon can occur. Roughly speaking, this happens when arbitrarily ... More
On varieties defined by large sets of quadrics and their application to error-correcting codesApr 29 2019Let $U$ be a $({ k-1 \choose 2}-1)$-dimensional subspace of quadrics defined on $\mathrm{PG}(k-1,{\mathbb F})$ with the property that $U$ does not contain reducible quadrics. Let $V(U)$ be the points of $\mathrm{PG}(k-1,{\mathbb F})$ which are zeros of ... More
Entrance and sojourn times for Markov chains. Application to $(L,R)$-random walksMar 30 2015In this paper, we provide a methodology for computing the probability distribution of sojourn times for a wide class of Markov chains. Our methodology consists in writing out linear systems and matrix equations for generating functions involving relations ... More
Families of twisted tensor product codesJul 06 2011Using geometric properties of the variety $\cV_{r,t}$, the image under the Grassmannian map of a Desarguesian $(t-1)$-spread of $\PG(rt-1,q)$, we introduce error correcting codes related to the twisted tensor product construction, producing several families ... More
Bayesian smoothing of dipoles in Magneto-/Electro-encephalographyFeb 12 2016We describe a novel method for dynamic estimation of multi-dipole states from Magneto/Electro-encephalography (M/EEG) time series. The new approach builds on the recent development of particle filters for M/EEG; these algorithms approximate, with samples ... More
On the most visited sites of planar Brownian motionFeb 08 2012Let (B_t : t > 0) be a planar Brownian motion and define gauge functions $\phi_\alpha(s)=log(1/s)^{-\alpha}$ for $\alpha>0$. If $\alpha<1$ we show that almost surely there exists a point x in the plane such that $H^{\phi_\alpha}({t > 0 : B_t=x})>0$, but ... More
QCD-like properties for anomalous dimensions in N=4 SYMOct 01 2008In this contribution it is shown how closed formulas for anomalous dimensions of two classes of operators in N=4 SYM can be derived, either by investigating the numerics or on the basis of QCD-inspired assumptions. We discuss the case of twist three "gauge" ... More
On $p$-adic differential equations on semistable varietiesMar 21 2010Nov 05 2012In this paper we prove a comparison theorem between the category of certain modules with integrable connection on the complement of a normal crossing divisor of the generic fiber of a proper semistable variety over a DVR and the category of certain log ... More
Fuchsian systems for Dotsenko-Fateev multipoint correlation functions and similar integrals of hypergeometric typeNov 23 2016The Dotsenko-Fateev integral is an analytic function of one complex variable expressing the amplitude in the 4-point correlator of the 2D conformal field theory. Dotsenko-Fateev found ODE of third order with Fuchsian singularities satisfied by their integral. ... More
A cool R Coronae Borealis star Z UMiJun 22 2007The high resolution spectra of a R CrB type star Z UMi are analysed. The atmospheric parameters of Z UMi are estimated: Teff=5250+/-250K and log g=0.5+/-0.3. This places Z UMi among the coolest R CrB stars. The hydrogen deficiency of Z UMi is confirmed. ... More
Optical spectroscopy of RU Cam, a pulsating carbon starJun 20 2007We analysed the high resolution spectra of a RU Cam, classified as W Vir type star. The atmospheric parameters of RU Cam were estimated Teff=5250K and log g=1.0. The hydrogen deficiency of RU Cam was not confirmed. The iron abundance, [Fe/H]=-0.37, is ... More
Two-Higgs-doublet models with Minimal Flavour ViolationSep 20 2010The tree-level flavour-changing neutral currents in the two-Higgs-doublet models can be suppressed by protecting the breaking of either flavour or flavour-blind symmetries, but only the first choice, implemented by the application of the Minimal Flavour ... More
Simultaneous flips on triangulated surfacesSep 14 2015We investigate a type of distance between triangulations on finite type surfaces where one moves between triangulations by performing simultaneous flips. We consider triangulations up to homeomorphism and our main results are upper bounds on distance ... More
Joint estimation of conditional quantiles in multivariate linear regression models. An application to financial distressAug 03 2018This paper proposes a maximum-likelihood approach to jointly estimate marginal conditional quantiles of multivariate response variables in a linear regression framework. We consider a slight reparameterization of the Multivariate Asymmetric Laplace distribution ... More
Reversible hydrogen storage by controlled buckling of graphene layersJan 06 2011We propose a multi-layer graphene-based device in which storage and release of atomic hydrogen is obtained by exploiting and controlling the corrugation of the layers. The proposal is based on density-functional simulations of hydrogen chemisorption on ... More
Reconciling Large And Small-Scale Structure In Twin Higgs ModelsNov 17 2016Aug 09 2017We study extensions of the Twin Higgs model that solve the Hierarchy problem and simultaneously address problems of the large- and small-scale structures of the Universe. Besides naturally providing dark matter (DM) candidates as the lightest charged ... More
Hardy-type inequalities for the Carnot-Carathéodory distance in the Heisenberg groupMar 20 2019Apr 01 2019In this paper we study various Hardy inequalities in the Heisenberg group $\mathbb H^n$, w.r.t. the Carnot-Carath\'eodory distance $\delta$ from the origin. We firstly show that the optimal constant for the Hardy inequality is strictly smaller than $n^2 ... More
Rationally cubic connected manifolds I: manifolds covered by linesMar 25 2010In this paper we study smooth complex projective polarized varieties (X,H) of dimension n \ge 2 which admit a dominating family V of rational curves of H-degree 3, such that two general points of X may be joined by a curve parametrized by V, and such ... More
Reasoning about exceptions in ontologies: from the lexicographic closure to the skeptical closureJul 08 2018Reasoning about exceptions in ontologies is nowadays one of the challenges the description logics community is facing. The paper describes a preferential approach for dealing with exceptions in Description Logics, based on the rational closure. The rational ... More
Rationally cubic connected manifolds IISep 20 2010We study smooth complex projective polarized varieties $(X,H)$ of dimension $ n \ge 2$ which admit a dominating family $V$ of rational curves of $H$-degree $3$, such that two general points of $X$ may be joined by a curve parametrized by $V$ and which ... More
A Restriction Theorem for Métivier GroupsNov 23 2012Jun 19 2013In the spirit of an earlier result of M\"uller on the Heisenberg group we prove a restriction theorem on a certain class of two step nilpotent Lie groups. Our result extends that of M\"uller also in the framework of the Heisenberg group.
Generically nef vector bundles on ruled surfacesMar 25 2018The present paper concerns the invariants of generically nef vector bundles on ruled surfaces. By Mehta - Ramanathan Restriction Theorem and by Miyaoka characterization of semistable vector bundles on a curve, the generic nefness can be considered as ... More
On the Limiting Behaviour of Needlets PolyspectraJul 17 2013This paper provides quantitative Central Limit Theorems for nonlinear transforms of spherical random fields, in the high frequency limit. The sequences of fields that we consider are represented as smoothed averages of spherical Gaussian eigenfunctions ... More
On differential operators of numerical semigroup ringsSep 28 2011If $S=<d_1,...,d_\nu>$ is a numerical semigroup, we call the ring $\C[S]=\C[t^{d_1},...,t^{d_\nu}]$ the semigroup ring of $S$. We study the ring of differential operators on $\C[S]$, and its associated graded in the filtration induced by the order of ... More
Schubert calculus on Newton-Okounkov polytopesDec 11 2018A Newton-Okounkov polytope of a complete flag variety can be turned into a convex geometric model for Schubert calculus. Namely, we can represent Schubert cycles by linear combinations of faces of the polytope so that the intersection product of cycles ... More