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Des corpus audiovisuels en Sciences Humaines et Sociales
No full textInternational audienceFilmer, annoter, analyser, partager : comment les sciences humaines et sociales s’emparent-elles des corpus audiovisuels ? Cet ouvrage collectif explore les usages scientifiques des vidéos dans la recherche contemporaine. À travers de nombreux exemples – du film amateur à la vidéo pédagogique, en passant par les archives et les captations de terrain –, il met en lumière les méthodes, outils et enjeux liés à l’analyse de documents audiovisuels numériques. Issu des travaux du consortium CANEVAS, ce livre propose un panorama inédit des pratiques actuelles et invite à repenser la place de l’image dans la production des savoirs
Entre incertitude subie et instabilité choisie. Les « expatrié·e·s » de Médecins Sans Frontières au prisme de la précarité
No full textInternational audienceThis article examines the ambivalent effects of the uncertainty surrounding humanitarian missions on expatriate workers of the organization Doctors Without Borders (MSF). When chosen, this uncertainty proves synonymous with freedom; when endured, it turns out to be a source of precarity. Based on a qualitative survey comprising sixty-eight interviews conducted between 2014 and 2023 with MSF expatriates, this article first shows how precarity is not just an objective question of resources in relation to the organization's employment conditions, but also the result of an interweaving of relative privileges that can cancel each other out (experience, profession, availability, geographical and social origin). It then reveals how the most vulnerable individuals are subjected by MSF's managerial policies to a double-edged sacrifice: intellectually enriching but economically weakening. Finally, it sheds light on how the organization renders itself precarious by the uncertainty and frequent turnovers generated by its mode of operation.Cet article vise à saisir les effets ambivalents de l'incertitude entourant les missions humanitaires sur les travailleurs·ses expatrié·e·s de l’organisation Médecins Sans Frontières (MSF). Tantôt choisie, cette incertitude se révèle synonyme de liberté ; tantôt subie, elle s’avère source de précarité. Basé sur une enquête qualitative comprenant soixante-huit entretiens menés entre 2014 et 2023 auprès d’expatrié·e·s MSF, cet article montre d'abord comment la précarité n'est pas seulement une question objective de ressources face aux conditions d’emploi de l’organisation mais le résultat d’un entrelacement de privilèges relatifs pouvant réciproquement s’annuler (expérience, métier, disponibilité, origine géographique et sociale). Il révèle ensuite comment les individus les plus vulnérables sont soumis par les politiques managériales de MSF à un sacrifice à double tranchant : enrichissant intellectuellement mais fragilisant économiquement. Il éclaire enfin la façon dont l'organisation se trouve elle-même précarisée par l’incertitude et les turnovers fréquents que son mode de fonctionnement génère
The random walk pinning model II: upper bounds on the free energy and disorder relevance
No full textThis article investigates the question of disorder relevance for the continuous-time Random Walk Pinning Model (RWPM) and completes the results of our companion paper. The RWPM considers a continuous time random walk X=(X_t)_{t\geq 0}, whose law is modified by a Gibbs weight given by \exp(\beta \int_0^T \mathbf{1}_{\{X_t=Y_t\}} dt), where Y=(Y_t)_{t\geq 0} is a quenched trajectory of a second (independent) random walk and \beta \geq 0 is the inverse temperature. The random walk Y has the same distribution as X but a jump rate \rho \geq 0, interpreted as the disorder intensity. For fixed \rho\ge 0, the RWPM undergoes a localization phase transition as \beta crosses a critical threshold \beta_c(\rho). The question of disorder relevance then consists in determining whether a disorder of arbitrarily small intensity \rho changes the properties of the phase transition. We focus our analysis on the case of transient \gamma-stable walks on \mathbb{Z}, i.e. random walks in the domain of attraction of a \gamma-stable law, with \gamma\in (0,1). In the present paper, we show that disorder is relevant when \gamma \in (0,\frac23], namely that \beta_c(\rho)>\beta_c(0) for every \rho>0. We also provide lower bounds on the critical point shift, which are matching the upper bounds obtained in our companion paper. Interestingly, in the marginal case \gamma = \frac23, disorder is always relevant, independently of the fine properties of the random walk distribution. When \gamma \in (\frac23,1), our companion paper proves that disorder is irrelevant (in particular \beta_c(\rho)=\beta_c(0) for \rho small enough). We provide here an upper bound on the free energy in the regime \gamma\in (\frac 2 3,1) that highlights the fact that although disorder is irrelevant, it still has a non-trivial effect on the phase transition, at any \rho>0
Targeted therapies overcome the poor prognosis of stereotyped Subset#2 chronic lymphocytic leukemia : a real-world multicentric study
No full textInternational audienceTO THE EDITOR:The outcome of patients with chronic lymphocytic leukemia (CLL) is known to be influenced by the mutational status of the immunoglobulin heavy-chain variable (IGHV) region [1]. In the past decade, it has been shown that a large part of CLL share B-cell receptor (BCR) sequence homologies, defining subsets of patients with similar clinical outcome [2]. The CLL Subset#2 (S#2), defined by the presence of the stereotyped IGHV3-21-derived rearrangement, with a short third complementarity-determining region (CDR3), has been linked to unfavorable prognosis. This translates in shorter time to first treatment, independently of other prognostic factors such as IGHV mutational status or genetic alterations [3, 4]. Despite S#2 being the most prevalent subset, few studies have investigated treatment responses and progression-free survival (PFS) in this context. Chemoimmunotherapy (CIT) is unsatisfactory in this group of patients [5, 6], but responses to targeted therapies (TT) have not been investigated. The aim of this study was to evaluate the outcome of patients with S#2 compared to patients with other IGHV3-21 subsets in the era of TT.A retrospective multicentric study was conducted across 31 French Innovative Leukemia Organization (FILO-CLL) affiliated centers in France, including patients diagnosed between 1998 and 2023. The study was declared to the Health data Hub according to French legislation. Patients identified with a productive IGHV3-21 rearrangement, available clinical and survival data, and no opposition to the study, were included. S#2, not-Subset#2 (nS#2) and IGHV mutational status were categorized according to the recommendations of the European Research Initiative on CLL (ERIC) [7]. Treatment strategies were CIT, Bruton Tyrosine Kinase inhibitors (BTKi), and B-Cell Lymphoma 2 inhibitors (BCL2i). Survival analysis, according to ERIC recommendations [7], considered borderline IGHV status as mutated. Time to first treatment (TTFT) and subsequent PFS analysis were performed using Kaplan-Meier estimation and log-rank test (R software, CRAN). Potential confounders, including age, sex, mutated (mIGHV) and unmutated (uIGHV) status, complex karyotype (CK) (≥3 abnormalities), high-CK (HCK) (≥5 abnormalities) and TP53</div
Surveillance Tricycle-OMS à Antananarivo (Madagascar): Circulation de souches de Escherichia coli productrices de β-lactamase à spectre étendu et des plasmides entre l’Homme, les poulets et l’environnement
No full textInternational audienceNo abstract availabl
Refined behavior and structural universality of the blow-up profile for the semilinear heat equation with non scale invariant nonlinearity
No full textInternational audienceWe consider the semilinear heat equation for a large class of non scale invariant nonlinearities of the form , where is Sobolev subcritical and is a slowly varying function (which includes for instance logarithms and their powers and iterates, as well as some strongly oscillating functions). For any positive radial decreasing blow-up solution, we obtain the sharp, global blow-up profile in the scale of the original variables , which takes the form: This estimate in particular provides the sharp final space profile and the refined space-time profile. As a remarkable fact and completely new observation, our results reveal a {\it structural universality} of the global blow-up profile, being given by the "resolvent" of the ODE, composed with a universal, time-space building block, which is the same as in the pure power case
D'une étiquette à l'autre. Des jeunesses entre pénal et handicap
No full textDossier thématique : Les parcours juvéniles sous le prisme du processus pénalInternational audienceThis article analyzes processes that shape the lives of disabled young people who also find themselves involved with the criminal justice system in France. It explores the social conditions and institutional stages that lead these individuals to trade one label for another and that differentiate their childhood experiences of the social world. Initially, the young people concerned are differentiated according to their basic characteristics and inclinations, and through their interactions with educational institutions. As medical and/or legal perspectives are brought to bear on the challenges they face in school and/or at home, these individuals find themselves singled out very early in their lives. Their differences are then reaffirmed within the youth justice system. Deemed special cases from the outset, they face criminal proceedings that differ from those faced by other youth due to reliance on special legal measures and “exceptional” professional services. Finally, the transition to adulthood represents a pivotal moment when a new series of distinctions play out, as institutions for adults with disabilities offer a way out of youth correctional facilities. Together, these factors contribute to the reconfiguration of social positions,with institutional verdicts helping to (re)produce an inherited or newly acquired working-class status.Cet article est centré sur l’analyse des processus qui scandent les parcours juvéniles lorsqu’un suivi pénal recoupe une prise en charge du handicap dans le contexte français. Il interroge les conditions sociales et étapes institutionnelles qui font passer les jeunes d’une étiquette à l’autre, et la façon dont elles façonnent la différenciation des expériences enfantines du monde social. Une première différenciation opère depuis les propriétés et les dispositions primaires des jeunes et de leur rencontre avec les institutions éducatives. L’existence des jeunes se singularise ainsi très tôt sous l’effet de la médicalisation et/ou de la judiciarisation des difficultés qu’ils rencontrent sur les scènes scolaires et/ou familiales. Cette différenciation s’actualise dans un second temps au sein même de la justice des mineurs. Le traitement pénal de cette jeunesse, déjà constituée comme spécifique, se distingue en effet des suivis pénaux des autres jeunes par l’usage dérogatoire des cadres judiciaires et des investissements professionnels « inhabituels ». Enfin, le seuil de la majorité constitue un moment charnière où se rejoue une nouvelle séquence de différenciation, les institutions du handicap pour adultes offrant une perspective de sortie des institutions pénales pour mineurs. L’ensemble contribue à la recomposition des positions sociales, les verdicts institutionnels contribuant à (re)produire une condition populaire héritée ou nouvellement acquise
High correlation between detection of dengue IgG from dried blood spots and serum using an indirect IgG ELISA assay: A validation study in Fortaleza, Brazil
No full textInternational audienceBackground Dengue virus (DENV) seroprevalence studies often rely on Enzyme-Linked Immunosorbent Assay (ELISA) testing of serum samples, but ELISA testing of dried blood spot (DBS) samples offer several advantages for field-based research in resource-limited settings. However, DBS’ limited sample volume can be challenging for test sensitivity, requiring validation studies with standard methods (e.g., analysis of serum through ELISAs or Plaque Reduction Neutralization Tests (PRNTs)). In preparation for a large cluster randomized controlled trial, we conducted a pilot study in 2019 to validate the use of DBS compared to serum samples for DENV IgG testing. We aimed to identify the optimal DBS dilution for IgG detection and to estimate the correlation, magnitude of agreement, and sensitivity and specificity of IgG detection in DBS versus serum samples. Methodology/Principal Findings We conducted this pilot validation study among 119 healthy participants in Fortaleza, Brazil to evaluate and optimize the detection of DENV IgG from DBS compared to serum. Each participant provided paired DBS and venous blood samples, which were evaluated for DENV IgG using the Panbio Dengue IgG indirect ELISA. DBS elution diluted 1:4 was optimal compared with serum results, with high correlation (r= 0.98) and near-perfect agreement (kappa = 0.95). At this dilution, DBS had a sensitivity of 100%, a specificity of 92.3%, a 97.9% positive predictive value, and a 100% negative predictive value compared with serum. Conclusions/Significance These results validate using DBS instead of serum for detection of prior dengue infection among similar populations in endemic regions, without sacrificing test sensitivity and specificity. The validity of using DBS for ELISA to detect prior dengue infection could have important implications for field-based research. A limitation to this study was that the potential for misclassification due to cross-reactivity (e.g., with Zika virus, Yellow Fever vaccine) was not assessed
Magneto-mechanical effects in a flexible magnetic system studied through combined MOKE magnetometry and mechanical testing
No full textInternational audienceWe explore the magnetic properties of a thin Co film deposited on Kapton® substrates using the magneto-optical Kerr effect in a longitudinal configuration. We developed a magnetometer integrated with a tensile testing machine to investigate magnetization reversal phenomena under applied strain. The tensile machine, custom-designed to fit the experimental constraints, applies uniaxial stress to the samples, facilitating the study of magnetoelastic effects. Calibration using digital image correlation ensures accurate strain measurements. Our findings demonstrate that the application of strain significantly influences the magnetization curves, highlighting the emergence of anisotropies and changes in coercive and saturation fields