New results on semileptonic b decays from LHCb

We report new measurements, based on the Run I dataset collected by the LHCb experiment, of the B0 mixing frequency Dm_d and the CKM matrix element |V_ub| using semileptonic b decays. The former is the most precise measurement ever performed; the latter represents the first determination of |V_ub| using a baryonic decay, and adds an important constraint on a possible explanation for the discrepancy between exclusive and inclusive determinations of this observable.Comment: Presentation at the DPF 2015 Meeting of the American Physical Society Division of Particles and Fields, Ann Arbor, Michigan, August 4-8, 201

The Algebra of Directed Acyclic Graphs

We give an algebraic presentation of directed acyclic graph structure, introducing a symmetric monoidal equational theory whose free PROP we characterise as that of finite abstract dags with input/output interfaces. Our development provides an initial-algebra semantics for dag structure

Studio di processi di gassificazione di fanghi da depurazione civile

Attualmente lo smaltimento dei fanghi da depurazione civile è reso sempre più problematico dalle normative vigenti che sono sempre più restrittive e limitano il ricorso ai metodi tradizionali (discarica, compostaggio, riutilizzo in agricoltura). Nell'ambito di uno studio finalizzato all'individuazione di sistemi di trattamento alternativi si inserisce il presente lavoro di tesi, il cui obiettivo è valutare l'applicazione del processo di gassificazione ai fanghi provenienti dalla depurazione di reflui civili. La sperimentazione è stata realizzata impiegando un impianto pilota di gassificazione a letto fisso in modalità up-draft. Lo studio si è articolato nelle seguenti attività: messa a punto, gestione, monitoraggio delle prestazioni dell’impianto pilota, campionamento e analisi del gas prodotto (syngas). Sulla base dei risultati sperimentali ottenuti sono stati impostati bilanci materiali e termici al fine di quantificare i flussi di materia e di energia connessi al processo per stimare le possibili configurazioni di recupero energetico

Posterior corneal surface stability after femtosecond laser-assisted keratomileusis

The purpose of this study was to evaluate posterior corneal surface variation after femtosecond laser-assisted keratomileusis in patients with myopia and myopic astigmatism. Patients were evaluated by corneal tomography preoperatively and at 1, 6, and 12 months. We analyzed changes in the posterior corneal curvature, posterior corneal elevation, and anterior chamber depth. Moreover, we explored correlation between corneal ablation depth, residual corneal thickness, percentage of ablated corneal tissue, and preoperative corneal thickness. During follow-up, the posterior corneal surface did not have a significant forward corneal shift: no significant linear relationships emerged between the anterior displacement of the posterior corneal surface and corneal ablation depth, residual corneal thickness, or percentage of ablated corneal tissue

Classical Logic with Mendler Induction

We investigate (co-)induction in Classical Logic under the propositions-as-types paradigm, considering propositional, second-order, and (co-)inductive types. Specifically, we introduce an extension of the Dual Calculus with a Mendler-style (co-)iterator that remains strongly normalizing under head reduction. We prove this using a non-constructive realizability argument.This is the author accepted manuscript. The final version is available from Springer via http://dx.doi.org/10.1007/978-3-319-27683-0_

Observer design for piecewise smooth and switched systems via contraction theory

The aim of this paper is to present the application of an approach to study contraction theory recently developed for piecewise smooth and switched systems. The approach that can be used to analyze incremental stability properties of so-called Filippov systems (or variable structure systems) is based on the use of regularization, a procedure to make the vector field of interest differentiable before analyzing its properties. We show that by using this extension of contraction theory to nondifferentiable vector fields, it is possible to design observers for a large class of piecewise smooth systems using not only Euclidean norms, as also done in previous literature, but also non-Euclidean norms. This allows greater flexibility in the design and encompasses the case of both piecewise-linear and piecewise-smooth (nonlinear) systems. The theoretical methodology is illustrated via a set of representative examples.Comment: Preprint accepted to IFAC World Congress 201