Point-record incentives, asymmetric information and dynamic data

Les politiques de sécurité routière utilisent souvent des mécanismes incitatifs basés sur les infractions pour améliorer le comportement des conducteurs. Ces mécanismes sont soit monétaires (amendes, primes d'assurance), soit non monétaires (permis à points). Nous utilisons des données québécoises couvrant une période allant de 1983 à 1996 pour analyser l'efficacité incitative de ces mécanismes. Nous analysons leurs propriétés théoriques par rapport au nombre de points associés aux infractions et par rapport au temps contrat. Ces propriétés sont ensuite testées empiriquement. Nous comparons l'efficacité globale des différents mécanismes incitatifs et nous relions les résultats obtenus avec les propriétés de la relation entre l'effort de conduite prudente et le risque d'infractions. Nous concluons à la présence d'aléa moral dans les données. Par ailleurs, la prime indicée sur les points introduite en 1992 a réduit de 15% la fréquence d'infractions.

A Vortex Method for Bi-phasic Fluids Interacting with Rigid Bodies

We present an accurate Lagrangian method based on vortex particles, level-sets, and immersed boundary methods, for animating the interplay between two fluids and rigid solids. We show that a vortex method is a good choice for simulating bi-phase flow, such as liquid and gas, with a good level of realism. Vortex particles are localized at the interfaces between the two fluids and within the regions of high turbulence. We gain local precision and efficiency from the stable advection permitted by the vorticity formulation. Moreover, our numerical method straightforwardly solves the two-way coupling problem between the fluids and animated rigid solids. This new approach is validated through numerical comparisons with reference experiments from the computational fluid community. We also show that the visually appealing results obtained in the CG community can be reproduced with increased efficiency and an easier implementation

Differences in triage and medical confidentiality between prisons of Belgium and the Netherlands

Objectives: The aim of this study is to describe the opinions of prison doctors, and to compare the primary health care in prisons between Belgium and the Netherlands. Methods: Structured interviews, audio-recorded and transcribed verbatim, were conducted with prison doctors in Dutch-speaking prisons in Flanders/Belgium and in the Netherlands. Two investigators analysed the content of the interviews and discussed each individual interview. Results: In total 37 interviews were conducted in 28 prisons (14 in each country). In Belgium, 14 of 17 prison doctors, compared to 1 of 12 in the Netherlands, experienced higher time pressure during their consultations in prison, compared to their private medical work (P < 0.001). In the Netherlands, compared to Belgium, there is more access to psychiatric support (14/14 vs 11/22, P = 0.002), psychological care (13/13 vs 7/22, P < 0.001), and interpreter facilities (15/22 vs 0/14, P < 0.001). Prison doctors in both countries agree that the possibility for a strictly personal encounter with the patient - without the presence of other medical staff - can be very useful (21/22 in Belgium vs 15/15 in the Netherlands). In Belgium, individual consultations with the detainee are not possible. Conclusions: Compared to the situation in the Netherlands, the medical work of prison doctors in Belgium is characterized by time pressure and lack of psychiatric and psychological support. The absence of interpreter facilities in Belgium handicaps the quality of the primary health care in prisons. In addition, the lack of private encounters with a doctor in Belgian prisons violates the patient rights of the detainee

Taxonomy and antimicrobial activities of a new Streptomyces sp. TN17 isolated in the soil from an oasis in Tunis

An actinomycete strain referred to as TN17 was screened for its antimicrobial activities. The taxonomic status of this strain was established. The organism was found to have morphological and chemotaxonomic characteristics typical of Streptomycetes. Based on the 16S rRNA nucleotide sequences, Streptomyces sp. TN17 was found to have a relationship with Streptomyces lilaceus, Streptomyces gobitricini and Streptomyces lavendofoliae. Combined analysis of the 16 S rRNA gene sequence (FN687757), phylogenetic analysis, fatty acids profile and physiological tests indicated that there are genotypic and phenotypic differences between TN17 and neighboring Streptomyces species’ neighbors. Therefore, TN17 is a novel species: Streptomyces sp. TN17 (=DSM 42020T=CTM50229T). A cultured extract of this strain inhibits the growth of several Gram positive and Gram negative bacteria and fungi

A Reduced Form Model of Default Spreads with Markov-Switching Macroeconomic Factors

An important research area of the corporate yield spread literature seeks to measure the proportion of the spread that can be explained by factors such as the possibility of default, liquidity, tax differentials and market risk. We contribute to this literature by assessing the ability of observed macroeconomic factors and the possibility of changes in regime to explain the proportion of yield spreads caused by the risk of default in the context of a reduced form model. For this purpose, we extend the Markov Switching risk-free term structure model of Bansal and Zhou (2002) to the corporate bond setting and develop recursive formulas for default probabilities, risk-free and risky zero-coupon bond yields as well as credit default swap premia. The model is calibrated with consumption, inflation, risk-free yields and default data for Aa, A and Baa bonds from the 1987-2008 period. We find that our macroeconomic factors are linked with two out of three sharp increases in the spreads during this sample period, indicating that the variations can be related to macroeconomic undiversifiable risk. The estimated default spreads can explain almost half of the 10 years to maturity industrial Baa zero-coupon yields in some regime. Much smaller proportions are found for Aa and A bonds with numbers around 10%. The proportions of default estimated with credit default swaps are higher, in many cases doubling those found with corporate yield spreads.Credit spread, default spread, Markov switching, macroeconomic factors, reduced form model of default, random subjective discount factor, credit default swap, CDS

Default Risk in Corporate Yield Spreads

An important research question examined in the recent credit risk literature focuses on the proportion of corporate yield spreads which can be attributed to default risk. Past studies have verified that only a small fraction of the spreads can be explained by default risk. In this paper, we reexamine this topic in the light of the different issues associated with the computation of transition and default probabilities obained with historical rating transition data. One significant finding of our research is that the estimated default-risk proportion of corporate yield spreads in highly sensitive to the term structure of the default probabilities estimated for each rating class. Moreover, this proportion can become a large fraction of the yield spread when sensitivity analyses are made with respect to recovery rates, default cycles in the economy, and information considered in the historical rating transition data.Credit risk, default risk, corporate yield spread, transition matrix, default probability, Moody's, Standard and Poor's, recovery rate, data filtration, default cycle

A Reduced Form Model of Default Spreads with Markov Switching Macroeconomic Factors

An important research area of the corporate yield spread literature seeks to measure the proportion of the spread explained by factors such as the possibility of default, liquidity or tax differentials. We contribute to this literature by assessing the ability of observed macroeconomic factors and the possibility of changes in regime to explain the proportion in yield spreads caused by the risk of default in the context of a reduced form model. For this purpose, we extend the Markov Switching risk-free term structure model of Bansal ad Zhou (2002) to the corporate bond setting and develop recursive formulas for default probabilities, risk-free and risky zero-coupon bond yields. The model is calibrated out of sample with consumption, inflation, risk-free yield and default data over the 1987-1996 period. Our results indicate that inflation is a key factor to consider for explaining default spreads during our sample period. We also find that the estimated default spreads can explain up to half of the 10 year to maturity Baa zero-coupon yield in certain regime with different sensitivities to consumption and inflation through time.Credit spread, default spread, Markov Switching, macroeconomic factors, reduced form model of default

Origin of the dunitic mantle-crust transition zone in the Oman ophiolite: The interplay between percolating magmas and high-temperature hydrous fluids

International audienc

Extreme geochemical variability through the dunitic transition zone of the Oman ophiolite: Implications for melt/fluid-rock reactions at Moho level beneath oceanic spreading centers

International audience15 The Maqsad area in the Oman ophiolite exposes a >300 m thick dunitic mantle-crust 16 transition zone (DTZ) that developed above a mantle diapir. The Maqsad DTZ is primarily 17 f "p " w h scattered chromite and chromite seams) and 18 " p g " which exhibit a significant lithological variability, including various 19 kinds of clinopyroxene-, plagioclase-, orthopyroxene-, amphibole (hornblende/pargasite)-20 bearing dunites. These minerals are interstitial between olivine grains and their variable 21 abundance and distribution suggest that they crystallized from a percolating melt. Generally 22 studied through in-situ mineral characterization, the whole rock composition of dunites is 23 poorly documented. This study reports on whole rock and minerals major and trace element 24 *Manuscript contents on 79 pure to variably impregnated dunites collected systematically along cross 2