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[en] This article propose a model of universe described by Friedmann-Lemaitre with positive curvature, where the repartition of Q.S.O. shows a singular zone, occupaying an equator of the spatial hypersphere. The possibility of a contact zone between matter and antimatter is also studied. Interpreted in this model the observations of Q.S.O. show a stratification parallel to equator. This universal anisotropy seems to be perceptible in the galactic repartition
[fr]L'article propose un modele d'univers de Friedmann-Lemaitre, a courbure positive, ou la repartition des Q.S.O. fait apparaitre une zone singuliere, occupant un equateur de l'hypersphere spatiale. Nous etudions la possibilite qu'il s'agisse d'une zone de contact matiere-antimatiere. Interpretees dans ce modele, les observations des Q.S.O. font apparaitre une stratification parallele a l'equateur. Cette anisotropie universelle semble perceptible jusque dans la repartition des galaxies
[en] Highlights: • The -canalizing functions generalize both canalizing and nested canalizing functions. • Every Boolean function has a unique extended monomial form and core polynomial. • We enumerate the -variable Boolean functions with canalizing depth . Boolean network models have gained popularity in computational systems biology over the last dozen years. Many of these networks use canalizing Boolean functions, which has led to increased interest in the study of these functions. The canalizing depth of a function describes how many canalizing variables can be recursively “picked off”, until a non-canalizing function remains. In this paper, we show how every Boolean function has a unique algebraic form involving extended monomial layers and a well-defined core polynomial. This generalizes recent work on the algebraic structure of nested canalizing functions, and it yields a stratification of all Boolean functions by their canalizing depth. As a result, we obtain closed formulas for the number of -variable Boolean functions with depth , which simultaneously generalizes enumeration formulas for canalizing, and nested canalizing functions.
[en] Recurrence of malignant ventricular arrhythmia is frequent in cardioverter-defibrillators related patients. The risk stratification is difficult, there are numerous electrocardiographic predictors but his sensibility and specificity are not absolute. The limit between normal and pathological is not defined, besides the complexity of ventricular arrhythmias. We expose different electrocardiographic predictors that can help to better individual risk stratification
[en] We present an experimental investigation of the different concentration build-up regimes encountered during a release of helium/air mixture in an empty enclosure without ventilation. The release is a vertical jet issuing from a nozzle located near the floor. The nozzle diameter, the flow rate and the composition of the injected mixture have been varied such that the injection Richardson number ranges from 6 x 10-6 to 190. The volume Richardson number, which gives the ability of the release to mix the enclosure content, ranges from 2 x 10-3 to 2 x 104. This wide range allowed reaching three distinct regimes: stratified, stratified with a homogeneous upper layer and homogenous. (authors)
[en] An algorithm for the calculation of the resistance between two arbitrary nodes in an arbitrary distance-regular resistor network is provided, where the calculation is based on stratification introduced in Jafarizadeh and Salimi (2006 J. Phys. A: Math. Gen. 39 1-29) and the Stieltjes transform of the spectral distribution (Stieltjes function) associated with the network. It is shown that the resistances between a node α and all nodes β belonging to the same stratum with respect to the α (Rαβ(i), β belonging to the ith stratum with respect to the α) are the same. Also, the analytical formulae for two-point resistances Rαβ(i), i=1,2,3, are given in terms of the size of the network and corresponding intersection numbers. In particular, the two-point resistances in a strongly regular network are given in terms of its parameters (v, κ, λ, μ). Moreover, the lower and upper bounds for two-point resistances in strongly regular networks are discussed
[en] A diverse and abundant organic-walled microphytoplankton assemblage, consisting of 49 species of acritarchs, prasinophyte phycomata and chitinozoans, was recovered from a 13.3 m-section of the Middle Devonian (Givetian) Arkona, Hungry Hollow andWidder formations at Hungry Hollow, Ontario, Canada. Close similarity exists between this assemblage and others described previously from the Givetian of North America. Marine palynofloras of comparable age from elsewhere in North America share between 59–96% of the species identified in the present assemblage, thus testifying to its stratigraphic-correlative applicability in a regional context. Species widely occurring in North America and typically Givetian (although not restricted therein) include: Arkonites bilixus, Cymatiosphaera canadense, Diexallophasis simplex, Duvernaysphaera angelae, D. tenuicingulata, Estiastra rhytidoa, Exochoderma arca, Gorgonisphaeridium inflatum, Hapsidopalla chela, Leiofusa pyrena, Muraticavea munifica, Oppilatala sparsa, Palacanthus ledanoisii, Polyedryxium ambitum, Staplinium cuboides, Tyligmasoma alargada, Uncinisphaera acantha, Veryhachium pastoris, Villosacapsula compta and V. rosendae. Palaeogeographically, Middle Devonian organic-walled microphytoplankton taxa display a conspicuous degree of cosmopolitanism, with many species shared with Laurasia (Laurentia, Avalonia, Baltica), Gondwana (principally Argentina, Ghana, Libya, Algerian Sahara, Western Australia) and Kazakhstan (northwestern China).
[es]Una asociación diversa de micropláncton de pared orgánica con gran abundancia de ejemplares, que está integrada por 49 especies de acritarcos, ficomas de prasinofitos y quitinozoos, fue obtenida en los materiales de la sección de 13,3 m de potencia del Devónico Medio (Givetiense) de Arkona, formaciones Hungry, Hollow y Widder, Ontario, Canadá. Esta asociación es muy parecida a otras que previamente se describieron en el Givetiense de Norte América. Algunas palinofloras marinas de otras partes de Norte América presentan asociaciones compuestas por un 59-96% de las especies que se estudian en este trabajo. De este modo, se pone de manifiesto su aplicación estratigráfica y de correlación en un contexto regional. Entre el conjunto de especies norteamericanas y típicamente givetienses (aunque no se encuentran restringidas a esta edad) identificadas están: Arkonites bilixus, Cymatiosphaera canadense, Diexallophasis simplex, Duvernaysphaera angelae, D. tenuicingulata, Estiastra rhytidoa, Exochoderma arca, Gorgonisphaeridium inflatum, Hapsidopalla chela, Leiofusa pyrena, Muraticavea munifica, Oppilatala sparsa, Palacanthus ledanoisii, Polyedryxium ambitum, Staplinium cuboides, Tyligmasoma alargada, Uncinisphaera acantha, Veryhachium pastoris, Villosacapsula compta y V. rosendae. Paleogeográficamente, los taxones microplanctónicos de pared orgánica del Devónico Medio que hemos identificados, son cosmopolitas en un alto grado, con muchas especies distribuidas por Laurasia (Laurentia, Avalonia, Báltica), Gondwana (principalmente Argentina, Ghana, Libia, el Sahara argelino, el Oeste de Australia) y Kazakhstan (noroeste de China
[en] Aim: To assess agreement between uroradiologists and urologists with regards to the timing of non-elective percutaneous nephrostomy (PCN) catheter insertion, and whether any delay produced unacceptable complications. Materials and methods: Standardized data collection forms detailing patient demographics, indications for PCN catheter insertion, blood results, procedural details, and immediate complications were completed by uroradiologists. At the time of referral, patients were stratified by both radiologists and urologists into three groups as follows: group 1 = PCN within 6 h; group 2 = PCN between 6 and 24 h; and group 3 = PCN between 24 and 48 h. Results: One hundred and eighteen non-elective PCN catheter insertions were performed over 2 years. Radiologists stratified 12 patients (10.2%) into group 1, 65 (55.1%) patients into group 2, and 41 (34.7%) patients into group 3. Urologists stratified 14 (11.9%) patients into group 1, 68 (57.6%) patients into group 2, and 36 (30.5%) patients into group 3. There was good agreement between radiologist and urologists (κ = 0.865) on stratification in all but nine (7.6%) cases. Ninety-four point one percent of PCN catheters were inserted within the timeframe stratified by radiologists and urologists, or sooner. Sepsis was associated with a shortened timeframe. Elevated international normalized ratio (INR; >1.5) resulted in an increased timeframe. A major complication rate of 3% is within recommended limits. Fourteen percent of PCN catheter insertions were inserted outside normal working hours. Urgency stratification has decreased the number of cases performed out of hours. Conclusion: Radiologists and urologists had good agreement on stratification with an acceptable major complication rate of 3%