Approche socio-anthropologique pour l’évaluation de la vulnérabilité sociale des zones protégées par les digues fluviales du Rhône aval

National audienceCette communication présente un modèle d’évaluation de la vulnérabilité sociale au risque inondation dans les zones protégées par des digues. Ce modèle articule trois échelles d’analyse. Une échelle macrosociologique porte sur les tendances économiques et socio-démographiques afin d’évaluer la vulnérabilité de grandes unités territoriales cohérentes. L’échelle mésoscopique fait référence à l’espace de groupes sociaux et de regroupements humains cohérents. À cette échelle, on privilégie le recours à l’enquête par questionnaires auprès de ménages en zone inondable. La méthodologie proposée s’oriente en particulier vers une approche comportementaliste afin d’évaluer la propension des individus à s’exposer au risque, en fonction également de leurs capacités d’adaptation, de leurs connaissances de l’inondation, des actions préventives adoptées par les ménages, etc. Enfin, à l’échelle microsociologique, au moyen d’entretiens semi-directifs, l’approche développée tente de cerner les conditions et restrictions à la mise en ½uvre de méthodes quantitatives pour l’évaluation de la vulnérabilité sociale. / A three-scaled model is assumed to estimate the social vulnerability of leveed areas. A macro scale refers to the economic and socio-demographic trends that allow to assess the vulnerability of coherent large urban areas. A meso scale refers to homogeneous communities or social groups. At this scale, the assessment of vulnerability proceeds by questionnaire surveys of households in flood risk areas. The methodology especially adopts a behavioural approach trying to estimate the propensity of people to self-exposure to risks, risk-taking practices, adaptive capacities, knowledge of flood process, the mitigation actions undertaken by householders, etc. At a micro scale, thanks to semi-structured interviews the methodology tries to assess the conditions and the restrictions to an assessment of vulnerability by means of quantitative methods

The singular continuous diffraction measure of the Thue-Morse chain

The paradigm for singular continuous spectra in symbolic dynamics and in mathematical diffraction is provided by the Thue-Morse chain, in its realisation as a binary sequence with values in $\{\pm 1\}$. We revisit this example and derive a functional equation together with an explicit form of the corresponding singular continuous diffraction measure, which is related to the known representation as a Riesz product.Comment: 6 pages, 1 figure; revised and improved versio

Using the Hadamard and related transforms for simplifying the spectrum of the quantum baker's map

We rationalize the somewhat surprising efficacy of the Hadamard transform in simplifying the eigenstates of the quantum baker's map, a paradigmatic model of quantum chaos. This allows us to construct closely related, but new, transforms that do significantly better, thus nearly solving for many states of the quantum baker's map. These new transforms, which combine the standard Fourier and Hadamard transforms in an interesting manner, are constructed from eigenvectors of the shift permutation operator that are also simultaneous eigenvectors of bit-flip (parity) and possess bit-reversal (time-reversal) symmetry.Comment: Version to appear in J. Phys. A. Added discussions; modified title; corrected minor error

Palindromic complexity of trees

We consider finite trees with edges labeled by letters on a finite alphabet $\varSigma$. Each pair of nodes defines a unique labeled path whose trace is a word of the free monoid $\varSigma^*$. The set of all such words defines the language of the tree. In this paper, we investigate the palindromic complexity of trees and provide hints for an upper bound on the number of distinct palindromes in the language of a tree.Comment: Submitted to the conference DLT201

Quantum chaos in the spectrum of operators used in Shor's algorithm

We provide compelling evidence for the presence of quantum chaos in the unitary part of Shor's factoring algorithm. In particular we analyze the spectrum of this part after proper desymmetrization and show that the fluctuations of the eigenangles as well as the distribution of the eigenvector components follow the CUE ensemble of random matrices, of relevance to quantized chaotic systems that violate time-reversal symmetry. However, as the algorithm tracks the evolution of a single state, it is possible to employ other operators, in particular it is possible that the generic quantum chaos found above becomes of a nongeneric kind such as is found in the quantum cat maps, and in toy models of the quantum bakers map.Comment: Title and paper modified to include interesting additional possibilities. Principal results unaffected. Accepted for publication in Phys. Rev. E as Rapid Com

IRMPD spectroscopy sheds new (InfraRed) light on the sulfate pattern of carbohydrates

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Time-to-birth prediction models and the influence of expert opinions

Preterm birth is the leading cause of death among children under five years old. The pathophysiology and etiology of preterm labor are not yet fully understood. This causes a large number of unnecessary hospitalizations due to high--sensitivity clinical policies, which has a significant psychological and economic impact. In this study, we present a predictive model, based on a new dataset containing information of 1,243 admissions, that predicts whether a patient will give birth within a given time after admission. Such a model could provide support in the clinical decision-making process. Predictions for birth within 48 h or 7 days after admission yield an Area Under the Curve of the Receiver Operating Characteristic (AUC) of 0.72 for both tasks. Furthermore, we show that by incorporating predictions made by experts at admission, which introduces a potential bias, the prediction effectiveness increases to an AUC score of 0.83 and 0.81 for these respective tasks

A Carbon Nanofilament-Bead Necklace

Carbon nanofilaments with carbon beads grown on their surfaces were successfully synthesized reproducibly by a floating catalyst CVD method. The nanofilaments hosting the pearl-like structures typically show an average diameter of about 60 nm, which mostly consists of low-ordered graphite layers. The beads with diameter range 150−450 nm are composed of hundreds of crumpled and random graphite layers. The mechanism for the formation of these beaded nanofilaments is ascribed to two nucleation processes of the pyrolytic carbon deposition, arising from a temperature gradient between different parts of the reaction chamber. Furthermore, the Raman scattering properties of the beaded nanofilaments have been measured, as well as their confocal Raman G-line images. The Raman spectra reveal that that the trunks of the nanofilaments have better graphitic properties than the beads, which is consistent with the HRTEM analysis. The beaded nanofilaments are expected to have high potential applications in composites, which should exhibit both particle- and fiber-reinforcing functions for the host matrixes