Pairwise Well-Formed Modes and Transformations

One of the most significant attitudinal shifts in the history of music occurred in the Renaissance, when an emerging triadic consciousness moved musicians towards a new scalar formation that placed major thirds on a par with perfect fifths. In this paper we revisit the confrontation between the two idealized scalar and modal conceptions, that of the ancient and medieval world and that of the early modern world, associated especially with Zarlino. We do this at an abstract level, in the language of algebraic combinatorics on words. In scale theory the juxtaposition is between well-formed and pairwise well-formed scales and modes, expressed in terms of Christoffel words or standard words and their conjugates, and the special Sturmian morphisms that generate them. Pairwise well-formed scales are encoded by words over a three-letter alphabet, and in our generalization we introduce special positive automorphisms of $F3$, the free group over three letters.Comment: 12 pages, 3 figures, paper presented at the MCM2017 at UNAM in Mexico City on June 27, 2017, keywords: pairwise well-formed scales and modes, well-formed scales and modes, well-formed words, Christoffel words, standard words, central words, algebraic combinatorics on words, special Sturmian morphism

Critical connectedness of thin arithmetical discrete planes

An arithmetical discrete plane is said to have critical connecting thickness if its thickness is equal to the infimum of the set of values that preserve its $2$-connectedness. This infimum thickness can be computed thanks to the fully subtractive algorithm. This multidimensional continued fraction algorithm consists, in its linear form, in subtracting the smallest entry to the other ones. We provide a characterization of the discrete planes with critical thickness that have zero intercept and that are $2$-connected. Our tools rely on the notion of dual substitution which is a geometric version of the usual notion of substitution acting on words. We associate with the fully subtractive algorithm a set of substitutions whose incidence matrix is provided by the matrices of the algorithm, and prove that their geometric counterparts generate arithmetic discrete planes.Comment: 18 pages, v2 includes several corrections and is a long version of the DGCI extended abstrac

The finite index basis property

We describe in this paper a connection between bifix codes, symbolic dynamical systems and free groups. This is in the spirit of the connection established previously for the symbolic systems corresponding to Sturmian words. We introduce a class of sets of factors of an infinite word with linear factor complexity containing Sturmian sets and regular interval exchange sets, namely the class of tree sets. We prove as a main result that for a uniformly recurrent tree set S, a finite bifix code X on the alphabet A is S-maximal of S-degree d if and only if it is the basis of a subgroup of index d of the free group on

Abcès de la prostate de découverte fortuite : A propos de deux cas

Introduction : l’abcès prostatique est une pathologie de plus en plus rare. Sa symptomatologie n’est pas spécifique. L’échographie endorectale et le scanner pelvien occupent une place de choix dans le diagnostic. Le traitement repose sur l’antibiothérapie adaptée et sur le drainage percutané par voie transpérinéale, transrectale ou endoscopique. Observation : nous rapportons deux cas d’abcès de prostate, l’un des patients est âgé de 47 ans et l’autre 61 ans. Dans les deux cas, le diagnostic a été de découverte fortuite en per opératoire. Le scanner abdominopelvien a posé le diagnostic de kyste de prostate chez l’un et une hypertrophie bénigne de la prostate chez l’autre par une échographie réno-vésico-prostatique. Le traitement a consisté en un drainage par chirurgie ouverte avec une antibiothérapie adaptée. L’évolution a été favorable dans les deux cas. Conclusion : l’abcès prostatique est une pathologie rare et sa symptomatologie clinique n’est pas spécifique. Dans notre cas, le diagnostic n’a pu être confirmé qu’en peropératoire et le traitement par chirurgie ouverte avec un bon résultat

Order in glassy systems

A directly measurable correlation length may be defined for systems having a two-step relaxation, based on the geometric properties of density profile that remains after averaging out the fast motion. We argue that the length diverges if and when the slow timescale diverges, whatever the microscopic mechanism at the origin of the slowing down. Measuring the length amounts to determining explicitly the complexity from the observed particle configurations. One may compute in the same way the Renyi complexities K_q, their relative behavior for different q characterizes the mechanism underlying the transition. In particular, the 'Random First Order' scenario predicts that in the glass phase K_q=0 for q>x, and K_q>0 for q<x, with x the Parisi parameter. The hypothesis of a nonequilibrium effective temperature may also be directly tested directly from configurations.Comment: Typos corrected, clarifications adde

Dépistage du VIH en salle d’accouchement à la maternité du Centre de Santé de Référence de la commune V Bamako

Objectifs : Evaluer l’impact du counseling pour le dépistage VIH en salle de travail chez les patientes n’ayant pas bénéficié de cette activité lors des CPN. Méthodes et matériels : L’étude s’est déroulée au CSRéf de la commune v de Bamako du 1er janvier au 31décembre 2014. L’échantillonnage était systématique, portait sur toutes les parturientes admises en salle de travail avec une dilatation cervicale à 4cm ou plus et dans le post- partum immédiat avec un âge gestationnel ≥ 28SA ou un poids fœtal ≥1000g. Le test par bandelette a été utilisé après consentement éclairé des patientes .La confirmation a été faite avec l’immunocomb II VIH1 et 2 Bi spot. Résultats :L’étude a rapporté que 4,34% (380) des parturientes n’ont pas fait le dépistage VIH lors du suivi prénatal. En salle d’accouchement, ces 380 parturientes ont bénéficié toutes d’un conseil dépistage volontaire au VIH. Nous avons enregistré 11 cas de refus. Sur les 369 parturientes ayant fait le test, 37 étaient positifs au VIH soit 10%. L’âge moyen était de 27ans ±07 ; non instruite (58,9%) vivant dans un régime polygamique (65,9) ; un suivi prénatal fait (95,12%) ; 93% suivi dans les structures citées PTME. Les antirétroviraux ont été administrés à toutes les mères et aux nouveau- nés vivants. Conclusion : Au regard de la fréquence élevée (10%) des cas positifs dans notre étude, il est nécessaire de poursuivre les activités de Conseil et Dépistage Volontaire en salle d’accouchement pour permettre à l’ensemble des femmes enceintes qui accouchent dans nos structures sanitaires de bénéficier des interventions de la PTM

Generic Continuous Spectrum for Ergodic Schr"odinger Operators

We consider discrete Schr"odinger operators on the line with potentials generated by a minimal homeomorphism on a compact metric space and a continuous sampling function. We introduce the concepts of topological and metric repetition property. Assuming that the underlying dynamical system satisfies one of these repetition properties, we show using Gordon's Lemma that for a generic continuous sampling function, the associated Schr"odinger operators have no eigenvalues in a topological or metric sense, respectively. We present a number of applications, particularly to shifts and skew-shifts on the torus.Comment: 14 page

A chemical survey of exoplanets with ARIEL

Thousands of exoplanets have now been discovered with a huge range of masses, sizes and orbits: from rocky Earth-like planets to large gas giants grazing the surface of their host star. However, the essential nature of these exoplanets remains largely mysterious: there is no known, discernible pattern linking the presence, size, or orbital parameters of a planet to the nature of its parent star. We have little idea whether the chemistry of a planet is linked to its formation environment, or whether the type of host star drives the physics and chemistry of the planet’s birth, and evolution. ARIEL was conceived to observe a large number (~1000) of transiting planets for statistical understanding, including gas giants, Neptunes, super-Earths and Earth-size planets around a range of host star types using transit spectroscopy in the 1.25–7.8 μm spectral range and multiple narrow-band photometry in the optical. ARIEL will focus on warm and hot planets to take advantage of their well-mixed atmospheres which should show minimal condensation and sequestration of high-Z materials compared to their colder Solar System siblings. Said warm and hot atmospheres are expected to be more representative of the planetary bulk composition. Observations of these warm/hot exoplanets, and in particular of their elemental composition (especially C, O, N, S, Si), will allow the understanding of the early stages of planetary and atmospheric formation during the nebular phase and the following few million years. ARIEL will thus provide a representative picture of the chemical nature of the exoplanets and relate this directly to the type and chemical environment of the host star. ARIEL is designed as a dedicated survey mission for combined-light spectroscopy, capable of observing a large and well-defined planet sample within its 4-year mission lifetime. Transit, eclipse and phase-curve spectroscopy methods, whereby the signal from the star and planet are differentiated using knowledge of the planetary ephemerides, allow us to measure atmospheric signals from the planet at levels of 10–100 part per million (ppm) relative to the star and, given the bright nature of targets, also allows more sophisticated techniques, such as eclipse mapping, to give a deeper insight into the nature of the atmosphere. These types of observations require a stable payload and satellite platform with broad, instantaneous wavelength coverage to detect many molecular species, probe the thermal structure, identify clouds and monitor the stellar activity. The wavelength range proposed covers all the expected major atmospheric gases from e.g. H2O, CO2, CH4 NH3, HCN, H2S through to the more exotic metallic compounds, such as TiO, VO, and condensed species. Simulations of ARIEL performance in conducting exoplanet surveys have been performed – using conservative estimates of mission performance and a full model of all significant noise sources in the measurement – using a list of potential ARIEL targets that incorporates the latest available exoplanet statistics. The conclusion at the end of the Phase A study, is that ARIEL – in line with the stated mission objectives – will be able to observe about 1000 exoplanets depending on the details of the adopted survey strategy, thus confirming the feasibility of the main science objectives.Peer reviewedFinal Published versio