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Programme dynamique générique pour l'ordonnancement d'intervalles avec contrainte de clique
No full textInternational audienceNous présentons un théorème général d'extension de programmes dynamiques pour des problèmes d'ordonnancement de tâches définis sur des graphes d'intervalles, en y ajoutant la contrainte selon laquelle au plus tâches peuvent être actives à tout instant . Nous parlerons alors de généralisation d'un problème initial vers sa variante intégrant des contraintes de cliques maximales locales. Pour un fixé, nous développons une méthode générale permettant d'adapter la résolution de à cette variante en temps polynomial.Notre approche suppose l'existence d'un programme dynamique résolvant le problème initial . Ce résultat s'applique à une large famille de problèmes d'ordonnancement et a notamment permis d'établir une résolution en temps polynomial pour un problème dont la complexité était jusqu'alors ouverte
La théorie de l’esprit chez les enfants autistes chinois : un développement différé et atypique
No full textInternational audienceTheory of Mind (ToM) development in autistic children is widely considered both delayed and deviant. However, such findings may be affected by methodological limitations related to high linguistic and executive burdens and the choice of scoring approaches. The present study employed an improved Low-Verbal ToM Scale With ExtEnded Trials (LV-ToM-SWEET) to assess ToM abilities in 46 Mandarin-speaking Chinese autistic children aged 4.0–12.3 years (Mean age = 7.3 yrs, SD = 1.8 yrs, 41 boys). Using the improved Exclude Coding Scheme (Sobel & Austerweil, 2016) in the Rasch analyses, we identified the following developmental sequence of ToM abilities: Diverse Desires (DD) < Diverse Beliefs (DB) < Content False Belief (CFB) < Knowledge Access (KA) < Explicit False Belief (EFB) < Hidden Emotion (HE). Results indicated that ToM development in autistic children was overall delayed, and with deviations in the later steps of ToM progression. These deviations, differing from those reported in previous autism studies, may reflect the impact of improved measurement approaches. Overall, the present study highlights the importance of improved tools and scoring approaches in capturing the delayed yet partially deviant ToM development in Mandarin-speaking Chinese autistic children. These tools offer promise for broader clinical application in the future.Le développement de la théorie de l’esprit (TE) chez les enfants autistes est généralement considéré comme à la fois différé et atypique. Cependant, ces conclusions peuvent être influencées par des limites méthodologiques liées à la complexité linguistique et exécutive des tâches ainsi qu’au choix des méthodes de cotation. La présente étude a utilisé une version améliorée de l’échelle Low-Verbal ToM, avec essais étendus (LV-ToM-SWEET), pour évaluer les capacités de TE chez 46 enfants autistes sinophones (mandarin), âgés de 4,0 à 12,3 ans (âge moyen = 7,3 ans, écart-type = 1,8 ans ; 41 garçons). Grâce à une version améliorée du schéma de cotation (Sobel & Austerweil, 2016) dans les analyses de Rasch, nous avons identifié la séquence développementale suivante : Désirs Diversifiés (DD) < Croyances Diversifiées (DB) < Contenu Fausse Croyance (CFC) < Accès à la Connaissance (AC) < Fausse Croyance Explicite (FCE) < Émotion Cachée (EC). Les résultats indiquent que le développement de la TE chez les enfants autistes est globalement différé, avec des déviations dans l'ordre d'acquisition des étapes du développement de la TE. Ces déviations, différentes de celles rapportées dans des études antérieures sur l’autisme, pourraient refléter l’impact de méthodes de mesure améliorées. Dans l’ensemble, la présente étude souligne l’importance d’outils et de méthodes de cotation plus performants pour rendre compte d’un développement de la TE à la fois différé et partiellement atypique chez les enfants autistes sinophones (mandarin). Ces outils apparaissent prometteurs pour une utilisation clinique plus large à l’avenir
“Rap as Gaeilge and Kneecap : Turning US Hip Hop Into a Tool For Irish Identity, Resistance, And Community Bridging in Post-Conflict Northern Ireland”
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Congruences for hook lengths of partitions
No full text14 pages, all comments are welcome ! arXiv admin note: text overlap with arXiv:2107.06793International audienceRecently, Amdeberhan et al. proved congruences for the number of hooks of fixed even length among the set of self-conjugate partitions of an integer , therefore answering positively a conjecture raised by Ballantine et al.. In this paper, we show how these congruences can be immediately derived and generalized from an addition theorem for self-conjugate partitions proved by the second author. We also recall how the addition theorem proved before by Han and Ji can be used to derive similar congruences for the whole set of partitions, which are originally due to Bessenrodt, and Bacher and Manivel. Finally, we extend such congruences to the set of -asymmetric partitions defined by Ayyer and Kumari, by proving an addition-multiplication theorem for these partitions. Among other things, this contains as special cases the congruences for the number of hook lengths for the self-conjugate and the so-called doubled distinct partitions
Supramolecular rotaxanes and polyrotaxanes as potential MRI contrast agents: a comprehensive 17O NMR and relaxometric study
No full textInternational audienceRotaxanes and polyrotaxanes made of substituted cyclodextrins (CDs) were designed as potential MRI contrast agents or bimodal optical and MRI probes. After characterization of the threading kinetics and the exact composition of the polyrotaxanes, their MRI properties have been investigated by 1 H relaxometry and 17 O NMR. We demonstrated that the relaxivity of these systems is increasing with increasing size (modified CDs, rotaxanes, and polyrotaxanes). 17 O NMR studies show that the various systems have similar water exchange rates, in the same range as that of Gd-DOTA-monoamide complexes. Interestingly, NMRD data of the smaller systems can be only analyzed by considering both local and global motions via Lipari-Szabo approach, underlining the importance of internal flexibility. On the other hand, the disubsituted rotaxane and the polyrotaxanes are highly rigid and can be characterized with a single rotational correlation time. Their relaxivity is considerably enhanced by a second sphere contribution which is strongly dependent on the structure. It increases from the rotaxane to the mono-and the disubstituted polyrotaxanes, and as expected, it diminishes with decreasing coverage of the axle. The fundamental understanding provided by this comprehensive study will help the design of versatile and more efficient supramolecular interlocked systems such as rotaxanes and polyrotaxanes for MRI applications.</div
Transgresiones de género y escritura torcida en “La niña” de Ana María Fuster Lavín
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Restricted mean survival time in cluster randomized trials with a small number of clusters: Improving variance estimation of the intervention effect from the pseudo-values regression
No full textInternational audienceIn randomized clinical trials with a time-to-event outcome, the intervention effect could be quantified by a difference in restricted mean survival time (ΔRMST) between the intervention and control groups, defined as the expected survival duration gain due to the intervention over a fixed follow-up period. In cluster randomized trials (CRTs), social units are randomized to intervention or control groups; the correlation between survival times of the individuals within the same cluster must be taken into account in the statistical analysis. In a previous work, we proposed the use of pseudo-values regression, based on generalized estimating equations (GEEs), for estimating ΔRMST in CRTs. We showed that this method correctly estimated the ΔRMST and controlled the type I error rate in CRTs with at least 50 clusters. Here, we propose methods for CRTs with a small number of clusters (≤50). We evaluated the performance of four bias-corrections of the GEE sandwich variance estimator of the intervention effect. We also considered the use of a Student t distribution as an alternative to the normal distribution of the GEE Wald test statistic for testing the intervention effect and constructing the confidence interval. With a simulation study, assuming proportional or non-proportional hazards, we showed that the Student t distribution outperformed the normal distribution in terms of type I error rate, and the Fay and Graubard bias-corrected variance led to an appropriate type I error rate whatever the number of clusters. Therefore, we recommend the use of the Fay and Graubard variance estimator combined with a Student t distribution for the pseudo-values regression to correctly estimate the variance of the intervention effect. Finally, we provide an illustrative analysis of the DEMETER trial evaluating the use of a specific endotracheal tube for subglottic secretion drainage to prevent ventilator-associated pneumonia, by comparing each of the methods considered
Auxiliary-Field Formalism for Higher-Derivative Boundary CFTs
No full textInternational audienceWe study the conformal field theory defined by the fourth-order operator on four-dimensional manifolds with boundaries, reformulating it through an auxiliary field so that the dynamics become second order. Within this framework, we compute the heat kernel of in flat space exactly, together with the associated Seeley-DeWitt coefficients for a broad class of non-standard boundary conditions. On curved backgrounds, we further construct the Weyl-invariant completion of the auxiliary field action with boundary terms and identify the corresponding conformal boundary conditions. Finally, we compute the boundary charges in the trace anomaly from the displacement operator correlators
Subdiffusive fractional limit of a jump-renewal equation
No full textIn this paper, we consider an age-structured jump model that arises as a description of continuous time random walks with infinite mean waiting time between jumps. We prove that under a suitable rescaling, this equation converges in the long time large scale limit to a time fractional subdiffusion equation