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Long-term outcome of oesophageal atresia in adolescence (TransEAsome): a national French cohort study protocol
No full textInternational audienceIntroduction The TransEAsome project, funded by the Agence Nationale de la Recherche, aims to evaluate the long-term outcomes of patients with oesophageal atresia (OA) between 13 and 14 years old and establish multiomics profiles using data from the world’s biggest OA registry.Methods and analysis TransEAsome is a national multicentre population-based cohort study recruiting participants from all qualified French centres for OA surgery at birth. The primary objective is to assess the prevalence of gastro-oesophageal reflux disease in adolescence among patients with OA, with several secondary objectives including the identification of risk factors and multiomic profiles from oesophageal biopsies and blood samples collected between 13 and 14 years old, compared with a control group. This comprehensive characterisation of phenotype and omic profiles aims to enhance the understanding of disease evolution in patients with OA and inform tailored care management strategies.Ethics and dissemination The study, coconstructed with input from patients, parents and research-expert adolescents, has obtained approval from the ethics research committee: Comité de protection des personnes Est II. Findings will be disseminated to various target audiences, including the scientific community, research participants, the patient community, the general public, regulatory authorities and policymakers. Data will be made available in a Findable, Accessible, Interoperable, Reusable format on the France Cohortes platform on study completion
Enumeration of walks in multidimensional orthants and reflection groups
No full text30 pagesWe consider (random) walks in a multidimensional orthant. Using the idea of universality in probability theory, one can associate a unique polyhedral domain to any given walk model. We use this connection to prove two sets of new results. First, we are interested in a group of transformations naturally associated with any small step model; as it turns out, this group is central to the classification of walk models. We show a strong connection between this group and the reflection group through the walls of the polyhedral domain. As a consequence, we can derive various conditions for the combinatorial group to be infinite. Secondly, we consider the asymptotics of the number of excursions, whose critical exponent is known to be computable in terms of the eigenvalue of the above polyhedral domain. We prove new results from spectral theory on the eigenvalues of polyhedral nodal domains. We believe that these results are interesting in their own right; they can also be used to find new exact asymptotic results for walk models corresponding to these nodal polyhedral domains
Functional characterization of a small gene family coding for putrescine hydroxycinnamoyltransferases, involved in phenolamide accumulation, in tomato
No full textInternational audiencePhenolamides are specialized metabolites widely distributed in the plant kingdom. Their structure is composedby the association of hydroxycinnamic acid derivatives to mono-/poly-amine through an amination catalyzed byN-hydroxycinnamoyltransferases enzymes. Tomato plants accumulate putrescine-derived phenolamides in theirvegetative parts. Recently, two first genes coding for putrescine-hydroxycinnamoyltransferase (PHT, Sol-yc11g071470 and Solyc11g071480) were identified in tomato and demonstrated to control the leaf accumulationof caffeoylputrescine in response to leafminer infestation. In this study, two additional genes (Solyc06g074710and Solyc11g066640) were functionally characterized as new tomato PHT. The substrate specificity and theexpression pattern in planta were determined for the four tomato PHT. Taken together the results give acomprehensive view of the control of the putrescine-derived phenolamide accumulation in tomato plant throughthe biochemical specificity and the spatial expression of this small family of PHT
Are all PTSD cases complex PTSD? Results from a latent profile analysis
No full textInternational audienceIntroduction: Recently, the ICD-11 has proposed the existence of both posttraumatic stress disorder (PTSD) and Complex PTSD (C-PTSD). However, empirical studies present conflictual results regarding a clear distinction between PTSD and C-PTSD. The aim of this study is to replicate previous works to shed light on the debate related to the distinction between PTSD and C-PTSD.Method: We recruited 115 patients (97 women, 18 men) suffering from PTSD consecutively during consultations at the trauma center. After providing consent, they filled out multiple questionnaires, including the International Trauma Questionnaire, the PTSD Checklist Scale, and the Childhood Trauma Questionnaire.Results: Latent Profile Analysis (LPA) identified four distinct latent classes that differed primarily in terms of the intensity of symptoms rather than the presence of specific symptoms. The classes were: (1) Severe C-PTSD, (2) Moderate C-PTSD, (3) Imbalanced C-PTSD, and (4) Low PTSD symptoms.Conclusion: Within our sample, we did not successfully distinguish patients suffering from PTSD and C-PTSD. Every patient seemed to suffer from C-PTSD except those with low PTSD symptoms. This supports a more dimensional understanding of patients suffering from PTSD
Optimisation of space-time periodic eigenvalues
No full textInternational audienceThe goal of this paper is to provide a qualitative analysis of the optimisation of space-time periodic principal eigenvalues. Namely, considering a fixed time horizon T and the d-dimensional torus T d , let, for any m ∈ L ∞ ((0, T ) × T d ), λ(m) be the principal eigenvalue of the operator ∂t -∆ -m endowed with (time-space) periodic boundary conditions. The main question we set out to answer is the following: how to choose m so as to minimise λ(m)? This question stems from population dynamics. We prove that in several cases it is always beneficial to rearrange m with respect to time in a symmetric way, which is the first comparison result for the rearrangement in time of parabolic equations. Furthermore, we investigate the validity (or lack thereof) of Talenti inequalities for the rearrangement in time of parabolic equations. The numerical simulations which illustrate our results were obtained by developing a framework within which it is possible to optimise criteria with respect to functions having a prescribed rearrangement (or distribution function).</div
Do tariff reductions alleviate energy poverty? Evidence for Sub-Saharan African countries
No full textInternational audienc
Influence of task context and task complexity on students’ task model quality, search behavior and search outcome
No full textInternational audienceSearching for information with a search engine requires students to develop a coherent representation of their search goal. According to the RESOLV model of purposeful reading, students can draw on clues from the task context and the task instructions. This study examined the influence of task context and task complexity on students’ initial task model, and the interplay between task context and students’ task models on search behavior and outcomes when using a search engine. Ninety university students searched for information for two simple and two complex search tasks, conducted in both academic and non-academic contexts. Students’ initial task models were mostly composed of core topic elements and of the surface-level actions required to search for information. Planning, regulation and standards of coherence were less frequently included in students’ initial task models. For simple tasks, higher standards of coherence promoted deeper navigation. For the complex tasks, the academic context and task complexity increased students’ standards of coherence and source processing. The academic context also fostered more navigation during simple tasks and improved search outcomes for students who struggled to understand the core topic in complex tasks. Theoretical and practical implications are discussed
Selected plant extracts and female fertility: role in the regulation of the hypothalamo-pituitary-ovarian axis in normal and pathological conditions
No full textInternational audienceFemale infertility, which affects 10–20% of couples worldwide, is a growing health concern in developing countries. It can be caused by multiple factors, including reproductive disorders, hormonal dysfunctions, congenital malformations and infections. In vitro and in vivo studies have shown that plant extracts regulate gonadotropin-releasing hormone, kisspeptin, and gonadotropin expression and/or secretion at the hypothalamic–pituitary level and modulate somatic and germ cells, such as steroidogenesis, proliferation, apoptosis, and oxidative stress at the ovarian level. In this review, we report evidence for the role of certain plant extracts or plant bioactive compounds in the regulation of the hypothalamic–pituitary-ovary axis and, consequently, for the treatment of female infertility. We will also summarize their possible involvement in ovarian disorders such as polycystic ovary syndrome (PCOS), premature ovarian failure (POF) and ovarian cancers
Cafard et cafarderie chez Rabelais, un propos si vilain
No full textInternational audienceLe mot cafard, probablement emprunté à l’arabe kāfir, « infidèle, qui change de religion », serait attesté en français avec ses dérivés dès la fin du xve siècle dans le sens de « faux dévot », mais les hébraïsants le pensaient d’origine hébraïque, stigmatisant celui qui dénonce ou trahit en se cachant. S’il est une injure chez les moralistes, prédicateurs et évangéliques avant la diffusion du luthéranisme en France, le terme entre ensuite dans le vocabulaire des luthériens et de leurs adversaires. Ce que Rabelais cache derrière « caphard » n’est pas toujours identifiable avec précision et l’insulte a pu changer de cible entre le premier et le dernier roman où il désignerait tous ceux qui persécutent au nom de la religion