Implications for liquidity from innovation and transparency in the European corporate bond market

This paper offers a new framework for the assessment of financial market liquidity and identifies two types: search liquidity and systemic liquidity. Search liquidity, i.e. liquidity in “normal” times, is driven by search costs required for a trader to find a willing buyer for an asset he/she is trying to sell or vice versa. Search liquidity is asset specific. Systemic liquidity, i.e. liquidity in “stressed” times, is driven by the homogeneity of investors - the degree to which one’s decision to sell is related to the decision to sell made by other market players at the same time. Systemic liquidity is specific to market participants’ behaviour. This framework proves fairly powerful in identifying the role of credit derivatives and transparency for liquidity of corporate bond markets. We have applied it to the illiquid segments of the European credit market and found that credit derivatives are likely to improve search liquidity as well as systemic liquidity. However, it is possible that in their popular use today, credit derivatives reinforce a concentration of positions that can worsen systemic liquidity. We also found that post-trade transparency has surprisingly little bearing on liquidity in that where it improves liquidity it is merely acting as a proxy for pre-trade transparency or transparency of holdings. We conclude that if liquidity is the objective, pre-trade transparency, as well as some delayed transparency on net exposures and concentrations, is likely to be more supportive of both search and systemic liquidity than post-trade transparency. JEL Classification: G14, G15, G18.Financial market functioning, liquidity, transparency, credit markets and financial innovation.

A fábula de Érica e a aventura tradutória: a tradução de Érica e i suoi fratelli, de Elio Vittorini

Introducing Erica e i suoi fratelli to the Brazilian lectors, I present also my own translation of this novel by Elio Vittorini.Ao apresentar Erica e i suoi fratelli ao público brasileiro, são tecidas considerações sobre a tradução deste romance de Elio Vittorini

Accuracy and Internal Fit of 3D printed Occlusal Splint, according to the printing position: A technique report

Compreender a importância de estratégias de impressão 3D é uma chave para obter aparelhos dentários estáveis, aperfeiçoados e consistentes utilizando tecnologias digitais. Este estudo tem como objetivo apresentar a influência da inclinação da impressão sobre a precisão do ajuste intraoral de placas de arco de cobertura total. As placas foram projetadas para dois pacientes com uso do software CAD e de uma impressora 3D SLA com diferentes inclinações (0, 30 e 90 graus), e o ajuste interno foi verificado na boca dos pacientes. Foi possível verificar diferenças entre o ajuste interno das placas, com os piores resultados para placas com inclinação de 90 graus, em­bora estudos mais detalhados sejam recomendados. DESCRITORES | Impressão tridimensional; Precisão; Medição das dimensões; Placa oclusal; Inclinação da Impressão.Understanding the importance of 3D printing strategies is a key to obtain predictable, optimized and consistent dental appliances using digital technologies. This study aims to present the influence of printing orientation on the intraoral fit of full arch coverage splints. Splints were designed for two patients using the CAD software and printed in a SLA 3D printer with different orientations (0, 30, and 90 degrees), and the internal fit was checked on patients’ mouth. Differen­ces between the fit of the splints were verified, with the worst results for 90º oriented splints, although more detailed studies are recommended by the authors. DESCRIPTORS | Three-Dimensional Printing; Accuracy; Dimensional Measurement; Occlusal Splint; Print Orientation

DE LA GEOGRAFÍA A LA LITERATURA: UN PERCURSO DE VIDA

Neste texto, a autora discorre sobre os momentos fundamentais do caminho por ela percorrido da geografia à literatura, destacando sempre a importância por ela dada a um real e profundo contato entre as diversas áreas do saber, única forma possível de entender uma realidade cada vez mais complexa e diversificada. Apresenta a seguir um texto, intitulado “Confiteor: confissões de uma imigrante italiana à cidade de São Paulo”, construído como um exemplo do encontro possível entre geografia e literatura.En este texto, la autora nos habla de los momentos fundamentales del camino por ella percorrido desde la geografia hasta la literatura, destacando siempre la importancia por ella dada a un efectivo y profundo contacto entre las diversas ramas del saber, la única forma posible de entender una realidad cada dia más compleja y diversificada. En seguida, nos presenta un texto, titulado “Confiteor: confesiones de una inmigrante italiana a la ciudad de São Paulo”, construído como un ejemplo del encuentro posible entre geografia y literatura.Dans ce texte, l’auteure trace les moments fondamentaux du chemin qu'elle a parcouru de la geographie à la litterature, en soulignant toujours l’importance qu’elle donne à un contact réel et profond entre les differentes disciplines, la seule forme possible pour comprendre une realité chaque jour plus complexe et diversifiée. Elle nous presente, ensuite, un texte, intitulé “Confiteor: les confessions d’une immigrée italienne à la ville de São Paulo”, construit comme un exemple de la rencontre possible entre la geographie et la litterature

Distribution with Quality of Service Considerations:The Capacitated Routing Problem with Profits and Service Level Requirements

Inspired by a problem arising in cash logistics, we propose the Capacitated Routing Problem with Profits and Service Level Requirements (CRPPSLR). The CRPPSLR extends the class of Routing Problems with Profits by considering customers requesting deliveries to their (possibly multiple) service points. Moreover, each customer imposes a service level requirement specifying a minimum-acceptable bound on the fraction of its service points being delivered. A customer-specific financial penalty is incurred by the logistics service provider when this requirement is not met. The CRPPSLR consists in finding vehicle routes maximizing the difference between the collected revenues and the incurred transportation and penalty costs in such a way that vehicle capacity and route duration constraints are met. A fleet of homogeneous vehicles is available for serving the customers. We design a branch-and-cut algorithm and evaluate the usefulness of valid inequalities that have been effectively used for the capacitated vehicle routing problem and, more recently, for other routing problems with profits. A real-life case study taken from the cash supply chain in the Netherlands highlights the relevance of the problem under consideration. Computational results illustrate the performance of the proposed solution approach under different input parameter settings for the synthetic instances. For instances of real-life problems, we distinguish between coin and banknote distribution, as vehicle capacities only matter when considering the former. Finally, we report on the effectiveness of the valid inequalities in closing the optimality gap at the root node for both the synthetic and the real-life instances and conclude with a sensitivity analysis on the most significant input parameters of our model

A New Method to Quantify X-ray Substructures in Clusters of Galaxies

We present a new method to quantify substructures in clusters of galaxies, based on the analysis of the intensity of structures. This analysis is done in a residual image that is the result of the subtraction of a surface brightness model, obtained by fitting a two-dimensional analytical model (beta-model or S\'ersic profile) with elliptical symmetry, from the X-ray image. Our method is applied to 34 clusters observed by the Chandra Space Telescope that are in the redshift range 0.02<z<0.2 and have a signal-to-noise ratio greater than 100. We present the calibration of the method and the relations between the substructure level with physical quantities, such as the mass, X-ray luminosity, temperature, and cluster redshift. We use our method to separate the clusters in two sub-samples of high and low substructure levels. We conclude, using Monte Carlo simulations, that the method recuperates very well the true amount of substructure for small angular core radii clusters (with respect to the whole image size) and good signal-to-noise observations. We find no evidence of correlation between the substructure level and physical properties of the clusters such as mass, gas temperature, X-ray luminosity and redshift. The scaling relations for the two sub-samples (high and low substructure level clusters) are different (they present an off-set, i.e., given a fixed mass or temperature, low substructure clusters tend to be more X-ray luminous), which is an important result for cosmological tests using the mass-luminosity relation to obtain the cluster mass function, since they rely on the assumption that clusters do not present different scaling relations according to their dynamical state.Comment: 13 pages, 17 figures, accepted for publication in ApJ (http://iopscience.iop.org/0004-637X/746/2/139/

A direct measurement of hierarchical growth in galaxy groups since z~1

We present the first measurement of the evolution of the galaxy group stellar mass function (GrSMF) to redshift z>~1 and low masses (M*>10^12 Msun). Our results are based on early data from the Carnegie-Spitzer-IMACS (CSI) Survey, utilizing low-resolution spectra and broadband optical/near-IR photometry to measure redshifts for a 3.6um selected sample of 37,000 galaxies over a 5.3 deg^2 area to z~1.2. Employing a standard friends-of-friends algorithm for all galaxies more massive than log(M*/Msun)=10.5, we find a total of ~4000 groups. Correcting for spectroscopic incompleteness (including slit collisions), we build cumulative stellar mass functions for these groups in redshift bins at z>0.35, comparing to the z=0 and z>0 mass functions from various group and cluster samples. Our derived mass functions match up well with z>0.35 X-ray selected clusters, and strong evolution is evident at all masses over the past 8 Gyr. Given the already low level of star formation activity in galaxies at these masses, we therefore attribute most of the observed growth in the GrSMF to group-group and group-galaxy mergers, in accordance with qualitative notions of hierarchical structure formation. Given the factor 3-10 increase in the number density of groups and clusters with M*>10^12 Msun since z=1 and the strong anticorrelation between star formation activity and environmental density, this late-time growth in group-sized halos may therefore be an important contributor to the structural and star-formation evolution of massive galaxies over the past 8 Gyr.Comment: 6 pages, 3 figures, submitted to ApJL. This paper is based on the Carnegie-Spitzer-IMACS (CSI) Survey, described in more detail at http://csi.obs.carnegiescience.ed