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Accompagner les habitant·es dans leur mobilité quotidienne. Défis et opportunités d’une méthode de parcours commenté
No full textInternational audienceCette présentation revient sur l'application d'une méthode de parcours commentés dans le cadre de deux thèses en géographie humaine et d'un programme ANR portant sur les mobilités quotidiennes dans les métropoles andines. Le processus de définition de cette méthode, les limites de son application et des explorations d'analyse et d'écriture à partir des données collectées sont étudiées
Explorer l’expérience des cyclistes à Bogotá. Choix d’itinéraire, interactions et corps en mouvement
No full textInternational audienceAbstract Research about urban mobility is increasingly focusing on the lived experience of mobility and its influence on the creation of practices and routines of mobility. We used mobile methods to study journeys in the making, with ride-along journeys, which we supplemented with interviews, designed to capture the discourse about everyday mobility by bike. The ride-along journeys enabled us to observe gestures and non-verbal interactions during the interviews and to create a dialogue between discourse and practice. This article presents the objectives and methodology of a thesis on cycling practices in Bogotá. We question how the lived experience shapes cycling practices and the routines that are implemented and the forms that these take in public space. This article takes three approaches to the lived experience and the forms it takes in everyday cycling: the route choice, the body’s mouvement in public space, and interactions with other users. We use extracts from the ride-along journeys to illustrate this point, highlighting the importance of taking into account a broader context – a social and human infrastructure – when designing public policy, which goes beyond the design of cycle facilities alone.Les recherches sur la mobilité urbaine s’intéressent de plus en plus à l’expérience vécue de celle-ci et son influence dans la constitution de pratiques et de routines de mobilité. Nous faisons appel aux méthodes mobiles qui étudient les déplacements en train de se faire, avec des parcours commentés, que nous complétons par des entretiens, destinés à saisir le discours porté sur la mobilité quotidienne à vélo. Les parcours commentés permettent d’observer les gestes et les interactions non-verbalisés pendant les entretiens et de créer un dialogue entre discours et pratique. Cet article présente donc les objectifs et la méthodologie mis en œuvre dans le cadre d’une thèse sur les pratiques du vélo à Bogotá. Nous nous demandons comment l’expérience vécue façonne les pratiques du vélo et les routines qui se mettent en œuvre et les formes que prennent celles-ci dans l’espace public. Cet article propose trois angles d’approche pour évoquer l’expérience vécue et les formes qu’elle prend dans la pratique quotidienne du vélo : le choix de l’itinéraire, le mouvement du corps dans l’espace traversé, et les interactions avec d’autres usagers. Nous illustrons le propos à partir d’extraits de parcours commentés, qui mettent en avant l’importance de la prise en compte d’un contexte large – d’une infrastructure sociale et humaine – au moment de concevoir la politique publique, qui dépasse la seule conception d’aménagements cyclables
SMT-Based and Fixed-Point Approaches for State Estimation in Max-Plus Linear Systems
No full textInternational audienceThis work builds on the seminal paper [1] and evaluates an existing method against a new approach for state estimation in Max-Plus Linear systems with bounded uncertainties. Traditional stochastic filtering is inapplicable to this system class, even though the posterior probability density function (PDF) can be computed. Previous research has shown a limited scalability of the disjunctive approach using difference-bound matrices. To address this, we investigate an alternative method recently explored in [2, 3], employing Satisfiability Modulo Theory (SMT) techniques, despite their NP-hard nature. The main novelty of this work is the proposal of a concise method based on fixed-point iteration in max-plus algebra, which is known to be a pseudo-polynomial time algorithm. To compare both approaches, a representative autonomous system is used in the paper to illustrate the basic computations. The efficiency of both approaches is compared through numerical experiments
La sociologie française du sport et l’introduction des travaux de Norbert Elias et Eric Dunning. Le rôle d'un lecteur et d'un traducteur. Entretien avec Jacques Defrance
No full textHuman pluripotent stem cell-derived hepatic progenitors exhibit a partially hypoimmunogenic phenotype and actively inhibit immune responses
No full textInternational audienceIntroduction : GStemHep cells are human cryopreserved hepatic progenitors derived from pluripotent of stem cells (GStem cells) using a cGMP-compliant protocol. They were highly effective in rescuing mice from acute liver failure. Methods : The objective of this study was to analyze the immunogenicity and immunoregulatory properties of GStemHep cells. Results : As compared to GStem cells, GStemHep cells showed complete loss of HLA-I (ABC) and they lacked of expression of HLA-II, HLA-G, HLA-E and PD-L1. GStemHep cells also showed increased expression of CD47, maintained high expression of indoleamine 2,3-dioxygenase (IDO) and heme oxygenase-1 (HO-1) and reduced expression of CD200. In comparison with GStem cells, GStemHep cultured in inflammatory conditions increased the expression of PD-L1, CD200, HO-1, HLA-E, CD47 and HLA-I (ABC) as well as maintained expression of IDO and were negative for HLA-II and HLA-G. GStemHep culture in basal or inflammatory conditions has a low or absent immunogenic activity on T cells, associated to a suppressive effect on proliferation partially mediated by IDO. We observed phagocytosis of GStemHep by macrophages that was partially inhibited by CD47 expression. NK cells were activated by resting GStemHep cells. Upon culture in inflammatory conditions that induced expression of HLA-I molecules in GStemHep cells NK cell activation was reduced. Thus, GStemHep cells are partially hypoimmune cells due to the expression of several immune checkpoint inhibitors and the absence of HLA-I molecules. In inflammatory conditions, the expression of several of these molecules was increased but also of HLA-I that could be immunogenic for T cells but it was inhibitory for NK cells. Discussion : GStemHep cells show a favorable immunological profile for their use as allogeneic off-the shelf treatment of liver diseases with loss of hepatocyte function
Iron deficiency in pregnancy and its association with blood lead and manganese levels in offspring in Benin, Sub-Saharan Africa
No full textInternational audienceIntroduction: The impact of prenatal iron deficiency (ID) on offspring's blood lead level (BLL) and blood manganese level (BML) in infancy remains poorly understood. This study aimed to assess associations between prenatal ID and BLL/BML in offspring in Benin. We also investigated associations between infant ID and corresponding BLL and BML in infants.Materials and methods: Data on hematological parameters, metal blood concentrations, and socioeconomic status were obtained from a prospective mother-child cohort study in Allada, Benin. Blood samples were collected during pregnancy (n = 501), at delivery (n = 501), and from 12-month-old infants (n = 501) to assess iron deficiency and haemoglobin concentration. Additionally, BML was analyzed for a subset of 12-month-old infants (n = 271), and BLL was determined for the full cohort of 12-month-old infants (n = 501). Associations between ID and metal concentrations were examined using logistic regressions.Results: Prenatal ID and IDA at the first and third antenatal care visit (ANC) were positively associated with infant BLL above 50 μg/L. Infants of mothers with prenatal ID and IDA had higher BLL. Moreover, prenatal ID and IDA at first and second ANC visits were positively associated with higher infant BML. In infancy, infants with ID and IDA had significantly higher BLL as compared to those without ID and IDA. Infant ID and IDA were positively associated with elevated BLL.Conclusion: Elevated BLL and BML in infants were positively associated with ID and/or IDA prenatally during at least one ANC visit, while in infancy, infant ID and IDA were positively associated with elevated BLL only. Infants with ID and IDA showed higher BLL but not BML. This suggests that ID prenatally and during infancy may contribute to high blood lead concentrations in infants, which can lead to neurotoxicity. Treating ID and IDA is critical to prevent toxicity caused by high BLL in infants
Exploring boundary conditions of sustained physical activity: implications for theory and practice.
No full textObjective: Sustained physical activity is crucial for health and is often referred to as 'physical activity maintenance.' However, this concept lacks consensus, possibly due limited study of the 'boundary conditions' under which this phenomenon occurs. This gap limits both theoretical development and interventional applications. This study examined the boundary conditions of two operational definitions of physical activity maintenance (activity threshold and timescale) and how their formulation impacts the detection of sustained physical activity phenomena. Methods: We analyzed 352 time series (length=182 days) of moderate-to-vigorous physical activity (MVPA) collected daily with Fitbit from participants in a weight loss intervention. Two activity thresholds were defined based on participants’ baseline intentions and physical activity levels: a) 150 minutes of MVPA/week for participants below this threshold at baseline (subsample BL-Inactive; n=101), and b) current level of MVPA/week for those exceeding 150 minutes of MVPA/week at baseline (subsample BL-Active; n=251). Regression trees were used to examine changes in physical activity trajectories using different boundary definitions of timescales (7, 14, 28, and 56 days). Results: At finer-grained timescales (7 days), physical activity exhibited repeated fluctuations, with sustained activity patterns in 27% of BL-Inactive and 5% of BL-Active participants. At coarser-grained timescales (56 days), activity trajectories were more stable, with sustained activity percentages increasing to 71% and 26%. Conclusions: Varying boundary conditions reveal different ways of conceptualizing sustained physical activity phenomena, leading to plausibly distinct conclusions about behavioral maintenance. These results highlight the importance of carefully studying boundary conditions as critical for robust theory and practice development
Anal incontinence in adults under 65 years: a survey based on social networks
No full textInternational audienceIntroduction: The frequency of anal incontinence in the general population is likely an underestimation, particularly among adults ≤65 years, for whom personal and professional considerations limit their utilization of medical care. The objective of this study was to assess the prevalence of anal incontinence in the young population and to address the reasons why such individuals do not seek care.Methods: This was a public health survey conducted using personal and professional social networks between April and November 2023. Participants between the ages of 18 and 65 were invited to respond a survey about their experience of anal incontinence (AI). The survey collected data on the Vaizey's score and the Anal Incontinence Quality of Life Index (FIQL).Results: Of the 481 individuals who completed the survey, 176 (36.6 %) reported experiencing AI. The majority of respondents exhibited mild incontinence (46 %), while 15.8 % experienced severe or major AI. Among those with AI, only 27.3 % consulted a physician, and in nearly 40 % of cases, no treatment was proposed. The primary reasons for not seeking consultation were embarrassment about the condition (63 %) and perceived stigma surrounding treatment (28 %), including a lack of awareness about available treatments. Multivariate analysis revealed that individuals between the ages of 26 and 45 were more likely to seek medical attention.Conclusion: The prevalence of incontinence of the anal nature among young adults remains significantly underestimated, despite its impact on their quality of life. Enhanced public health communication regarding the management of incontinence, particularly among young individuals and healthcare providers, is imperative
Genome-wide transcriptional silencing and mRNA stabilization allow the coordinated expression of the meiotic program in mice
No full textInternational audienceThe transcriptional dynamic of mammalian cells when these transit from the ubiquitous mitotic to a meiotic-specific program is key to understand this switch central to sexual reproduction. By quantifying active RNA polymerase II and nascent transcripts using single cell dataset and ethynyl-uridine pool-down with sorted cells from synchronized testes, we detailed the transcriptional activity of murine male germ cells. When spermatogonia differentiate, transcription slows down, reaching minimal activity at meiotic entry and resumes during pachytene stage. This event, we termed EMLT (for early meiotic low transcription), is distinct from the silencing of sex chromosomes as it is independent of Setdb1, though it is accompanied by the same chromatin mark, H3K9me3. EMLT is delayed in Stra8KO but occurs in mutants altering meiotic chromosome structure or double-strand break formation or repair. By comparing transcript abundance and nascent transcription we unveil a massive event of messenger RNA stabilization that parallels EMLT. Altogether our data indicate that meiosis is initiated with a nearly silent genome, and we propose that the stabilization of transcripts at that time facilitates the meiotic entry by synchronizing the expression of several meiotic subprograms
Prévalence de l’automédication chez les transplantés rénaux : une étude transversale monocentrique
No full textInternational audienceSelf-medication among kidney transplant patients may pose a risk to the graft. This study examined the prevalence of self-medication in patients who had undergone kidney transplantation. These patients, receiving immunosuppressive therapy, are informed during post-transplant therapeutic education about the risks associated with drug interactions. This prospective single-center study, including 66 patients, shows that 80.3% of participants reported self-medicating one month after hospital discharge, with 18.2% engaging in practices deemed “risky”. Self-medication mainly involved analgesics, including non-steroidal anti-inflammatory drugs (NSAIDs), sleeping pills, and treatments for heartburn, such as proton pump inhibitors (PPIs) and antacids. The results show that neither age, sex, education level, nor employment status were significantly associated with risky self-medication. However, the high prevalence of this practice highlights the need for increased patient awareness of potential dangers, particularly those related to NSAIDs and drug interactions. PPIs, often used for heartburn, carry interaction risks, especially with tacrolimus, and prolonged use may lead to kidney complications. Herbal medicine, also used by some patients, may present interaction risks with immunosuppressants. The study suggests strengthening patient therapeutic education (PTE) by emphasizing the risks of inappropriate self-medication and proposes safe alternatives, such as antacids, or seeking medical consultation. These results, based on self-reported data, may underestimate the true prevalence of self-medication. The study recommends continuous vigilance and further research to assess these practices over the long term.La pratique de l’automédication chez les patients transplantés rénaux peut présenter un risque pour le greffon. Cette étude a examiné la prévalence de l’automédication chez les patients ayant reçu une transplantation rénale.Ces patients, sous traitement immunosuppresseur, sont informés, lors de l’éducation thérapeutique après la transplantation, des risques associés aux interactions médicamenteuses. Cette étude prospective monocentrique incluant 66 patients montre que 80,3 % des participants déclarent avoir pratiqué l’automédication un mois après leur sortie d’hospitalisation, dont 18,2 % avec des pratiques jugées « à risque ». Les automédications concernaient principalement les antalgiques dont les anti-inflammatoires non stéroïdiens (AINS), les somnifères, et les traitements pour le pyrosis, incluant les inhibiteurs de pompes à protons (IPP) et les pansements gastriques. Les résultats montrent que ni l’âge, ni le sexe, ni le niveau d’éducation ou le statut professionnel ne sont significativement associés à l’automédication à risque. Cependant, la prévalence élevée de cette pratique souligne la nécessité d’une sensibilisation accrue des patients greffés aux dangers potentiels, notamment liés aux AINS et aux interactions médicamenteuses. Les IPP, souvent utilisés pour les brûlures d’estomac, présentent des risques d’interaction, en particulier avec le tacrolimus, et leur usage prolongé peut conduire à des complications rénales. La phytothérapie, également pratiquée par certains patients, présenterait des risques d’interactions avec les immunosuppresseurs.L’étude suggère de renforcer l’éducation thérapeutique du patient (ETP) en insistant sur les risques de l’automédication inappropriée et propose des alternatives sûres, comme les pansements gastriques, ou d’avoir recours à une consultation médicale. Ces résultats, basés sur des autodéclarations, pourraient sous-estimer la prévalence réelle de l’automédication. L’étude recommande une vigilance continue et des recherches supplémentaires pour évaluer ces pratiques sur le long terme