Singularidades químico-farmacêuticas da ficção Queirosiana (2ª Parte)

Da análise efectuada à presença e ao papel da Química e da Farmácia na escrita realista de Eça de Queirós, resultou uma primeira parte deste artigo, que inclui as secções “Águas minerais e antiácidos” e “Metais pesados”. Nesta segunda parte, apresentam-se as secções “Fármacos e preparações de origem vegetal”, “Óleos, solventes e produtos resinosos” e “Outros fármacos e produtos químicos”

Rates of convergence to scaling profiles in a submonolayer deposition model and the preservation of memory of the initial condition

We establish rates of convergence of solutions to scaling (or similarity) profiles in a coagulation type system modelling submonolayer deposition. We prove that, although all memory of the initial condition is lost in the similarity limit, information about the large cluster tail of the initial condition is preserved in the rate of approach to the similarity profile. The proof relies in a change of variables that allows for the decoupling of the original infinite system of ordinary differential equations into a closed two-dimensional nonlinear system for the monomer--bulk dynamics and a lower triangular infinite dimensional linear one for the cluster dynamics. The detailed knowledge of the long time monomer concentration, which was obtained earlier by Costin et al. in (O. Costin, M. Grinfeld, K.P. O'Neill and H. Park, Long-time behaviour of point islands under fixed rate deposition, Commun. Inf. Syst. 13, (2), (2013), pp.183-200) using asymptotic methods and is rederived here by center manifold arguments, is then used for the asymptotic evaluation of an integral representation formula for the concentration of $j$-clusters. The use of higher order expressions, both for the Stirling expansion and for the monomer evolution at large times allow us to obtain, not only the similarity limit, but also the rate at which it is approached.Comment: Revised according to referee's suggestions; to be published in SIAM J. Math. Ana

On the convergence to critical scaling profiles in submonolayer deposition models

In this work we study the rate of convergence to similarity profiles in a mean field model for the deposition of a submonolayer of atoms in a crystal facet, when there is a critical minimal size $n\geq 2$ for the stability of the formed clusters. The work complements recently published related results by the same authors in which the rate of convergence was studied outside of a critical direction $x=\tau$ in the cluster size $x$ vs. time $\tau$ plane. In this paper we consider a different similarity variable, $\xi := (x-\tau)/\sqrt{\tau}$, corresponding to an inner expansion of that critical direction, and prove the convergence of solutions to a similarity profile $\Phi_{2,n}(\xi)$ when $x, \tau\to +\infty$ with $\xi$ fixed, as well as the rate at which the limit is approached.Comment: Dedicated to the memory of Jack Car

Singularidades químico-farmacêuticas da ficção Queirosiana

A obra ficcional de Eça de Queirós é rica em detalhes descritivos que se estendem ao domínio das Ciências Naturais. A Química, quer pela via farmacêutica quer pela das banais aplicações domésticas, não escapou à pena realista do autor, contribuindo de forma marcante para a composição do retrato que este nos quis deixar da sociedade portuguesa de finais de Oitocentos: a partir da sua obra ficcional é possível elaborar um rol de cerca de quatro dezenas de compostos, produtos e preparações químicas e farmacêuticas. Nesta perspectiva, e a título de exemplo, a causa da morte de Juliana – a criada de Luísa n’ O Primo Basílio e uma das personagens mais fascinantes, e hediondas, da obra de Eça – é-nos apresentada através de uma narrativa de teor científico, constituindo um caso paradigmático na literatura realista universal. Este e outros casos queirosianos são analisados ao longo deste artigo que, por limitações de espaço, foi divido em duas partes. Na primeira, que agora se publica, apresentam-se as secções “Águas minerais e antiácidos” e “Metais pesados”. Na segunda, apresentar-se-ão as secções “Fármacos e preparações de origem vegetal”, “Óleos, solventes e produtos resinosos” e “Outros fármacos e produtos químicos”

Judicial Risk and Credit Market Performance: Micro Evidence from Brazil Payroll Loans

A large body of literature has stressed the institution-development nexus as critical in explaining differences in countries' economic performance. The empirical evidence, however, has been mainly at the aggregate level, associating macro performance with measures of quality of institutions. This paper, by relating a judicial decision on the legality of payroll debit loans in Brazil to bank-level decision variables, provides micro evidence on how creditor legal protection affects market performance. Payroll loans are personal loans with principal and interests payments directly deducted from the borrowers' payroll check, which, in practice, makes a collateral out of future income. In June 2004, a high-level federal court upheld a regional court ruling that had declared payroll deduction illegal. Using personal loans without payroll deduction as a control group, we assess whether the ruling had an impact on market performance. Evidence indicates that it had an adverse impact on risk perception, interest rates, and amount lent.

SketchyDynamics: A Library for the Development of Physics Simulation Applications with Sketch-Based Interfaces

Sketch-based interfaces provide a powerful, natural and intuitive way for users to interact with an application. By combining a sketch-based interface with a physically simulated environment, an application offers the means for users to rapidly sketch a set of objects, like if they are doing it on piece of paper, and see how these objects behave in a simulation. In this paper we present SketchyDynamics, a library that intends to facilitate the creation of applications by rapidly providing them a sketch-based interface and physics simulation capabilities. SketchyDynamics was designed to be versatile and customizable but also simple. In fact, a simple application where the user draws objects and they are immediately simulated, colliding with each other and reacting to the specified physical forces, can be created with only 3 lines of code. In order to validate SketchyDynamics design choices, we also present some details of the usability evaluation that was conducted with a proof-of-concept prototype

A Dain Inequality with charge

We prove an upper bound for angular-momentum and charge in terms of the mass for electro-vacuum asymptotically flat axisymmetric initial data sets with simply connected orbit space