Sur l'utilisation de l'analyseur thermo-gravimétrique pour l'investigation incendie.

Lors du développement d'une nouvelle méthode d'investigation post-incendie recourant à la simulation numérique en vue de reconstituer le sinistre, la notion de points de comparaison avait été définie (travaux de thèse de M. Suzanne, LCPP). L'objectif du travail présenté ici est alors de développer cette approche pour permettre à l'investigateur de définir des niveaux de températures et de temps d'exposition atteints en différents points de la scène d'incendie,en s'appuyant sur les états de dégradation relevés sur divers éléments. Pour ce faire, l'utilisation de l'analyseur thermogravimétrique (ATG) a été proposée. Cet analyseur permettant la détermination des mécanismes de dégradation thermique du matériau étudié, l'idée initiale est donc de comparer les résultats ATG obtenus sur un matériau dégradé thermiquement lors de l'incendie avec des résultats obtenus pour ce même matériau non dégradé. Les différences relevées sur les thermogrammes devraient alors permettre de conclure sur les niveaux de température rencontrés. Cette méthodologie a été appliquée sur divers matériaux, tels que le PVC, l'ABS ou le PET, qui ont été dégradés soit « artificiellement » au four tubulaire ou au cône calorimètre soit lors d'essais feux grandeur réelle.Les résultats obtenus lors de cette campagne de mise au point et validation de méthode, sont très encourageants quant à la possibilité d'obtenir une estimation de la température atteinte dans l'environnement de l'objet lors de l'incendie. La seconde partie de ce travail consiste en la détermination du temps d'exposition à la sollicitation thermique de l'objet étudié grâce à une approche iso-conversionnelle de sa cinétique de dégradation. Cette approche est cependant toujours en cours de développement

COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study

Background: The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms. Methods: International, prospective observational study of 60 109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms. Results: ‘Typical’ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (≤ 18 years: 69, 48, 23; 85%), older adults (≥ 70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each P < 0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country. Interpretation: This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men

Modélisation des dégradations relevées après sinistre, couplage avec une campagne expérimentale pour la validation d'une méthodologie d'investigations post-incendie par simulation numérique

In the framework of complex fire investigations, an advantage of numerical tool, here Fire Dynamics Simulator (FDS), is the ability of assessing the relevance of numerous hypothesis stated by the investigator. However, to determine the scenario that best reproduces the conflagration, comparison points have to be defined between the fire scene and the final state of simulations.The aim of this work is to determine the thermal insult sustained by various objects of the fire scene to compare it with numerical results. The apparatus mainly used to determine the thermal degradation mechanisms is the thermo-gravimetric analyser (TGA). Then, the following experimental method in proposed. TGA results obtained for a virgin sample of the studied element are compared with those obtained for a burnt sample of the same element. The differences outlined allow an estimation of the temperature levels reached in the burnt sample environment during the fire. However, no quantification of fire duration is possible through this method.In order to obtain such data, a model based on the kinetics of the thermal degradation reaction is developed on Scilab. The aim of this program is to compare the theoretical reaction progress reached for temperatures extracted from each scenario of numerical simulations with the reaction progress of the burnt material. To obtain those values, the iso-conversional approach of the Arrhénius law is considered. Finally, the multiplication of comparison points on the fire scene allows the selection of the most appropriate FDS scenario.Dans le cadre d’investigations post-incendie complexes, l'avantage de l’outil numérique, ici Fire Dynamics Simulator (FDS), est la possibilité d'évaluer la pertinence de plusieurs hypothèses formulées par l'enquêteur. Afin de déterminer le scénario reproduisant au mieux le déroulement du sinistre, des points de comparaison doivent être définis entre la scène d’incendie et l’état final des simulations.Le but des travaux est alors de déterminer la sollicitation thermique subie par divers éléments de la scène d'incendie pour la comparer aux résultats des simulations. L'outil utilisé pour la détermination des mécanismes réactionnels de dégradation thermique étant l'analyseur thermogravimétrique (ATG), la méthode expérimentale suivante est proposée. Les résultats ATG obtenus sur un matériau dégradé lors de l'incendie sont comparés à ceux pour ce même matériau non dégradé. Les différences relevées permettent d'estimer les niveaux de température atteints dans l’environnement du matériau dégradé. Toutefois, aucune quantification du temps d’exposition ne peut être obtenue.Afin d'obtenir cette donnée, un modèle basé sur la cinétique de réaction des matériaux est développé avec Scilab. L'objectif est de comparer un état d'avancement de la réaction de dégradation thermique théorique avec l'état d'avancement du matériau dégradé. L'approche isoconversionnelle de la loi d'Arrhénius est considérée. Les données d'entrée du modèle sont les courbes de température en fonction du temps extraites de FDS pour tous les scénarios modélisés et les propriétés cinétiques du matériau. La multiplication des points de comparaison permet de sélectionner le scénario FDS le plus approprié

Counseling Parents About Child Feeding: a Qualitative Evaluation of French Healthcare and Childcare Professionals’ Experiences and Their Perception of a Brochure Containing New Recommendations

Background: Parents are crucial in establishing their children's eating habits, and healthcare (HCPs) and childcare professionals (CCPs) can provide meaningful and trusted guidance on feeding, especially in the 0-3-year-old period. With the upcoming release of the official brochure containing the new child feeding recommendations in France, this study aims to: 1) assess professionals’ practices and perceptions regarding their communication with parents on child feeding and 2) evaluate their impressions of the new brochure.Methods: A 15-page brochure containing updated child feeding recommendations for children 0-3 years old was developed by the French public health agency. Online semi-structured interviews were conducted with professionals (n=21), including 13 pediatricians and general practitioners (HCPs), nine childcare assistants or professionals (CCPs) two weeks after they were provided with this brochure to read. The interview guide was developed and piloted with other professionals (n=3) prior to these interviews. Interview data were transcribed verbatim and analyzed thematically using an inductive approach.Results: While HCPs and CCPs mostly communicate orally with parents, both acknowledged that the brochure might be a helpful supplement, especially for CCPs to legitimize their advice to parents. For HCPs, giving the brochure to parents may help provide systematic advice and save time during consultations. Professionals serving parents of lower socioeconomic status would prefer a supplement with less text and more illustrations. In general, the messages were perceived to be easily understandable but providing detachable cards to distribute according to the child’s age would facilitate information dissemination and might be more useful to parents. Professionals reported that lack of training, the circulation of contradictory information, and language barriers were common challenges. Professionals suggested that short texts with more references and visual aids could improve the brochure.Conclusions: French professionals welcome the new official brochure as a means to spread updated child feeding recommendations, but it could be modified to be better adapted to their needs of communication with parents and to facilitate the relay of information. Providing updated and consistent information to parents should be considered a priority for public health stakeholders toward increased adherence to new recommendations

Qualitative Evaluation, with French Healthcare and Childcare Professionals, of a Brochure Containing the Latest Official Child Feeding Recommendations to Help Prevent Childhood Obesity

Meeting abstract number 4 in the 30. Annual Congress of European Chilhood Obesity Group (ECOG), 2021/11/10-13, Budapest (Hungary)

Qualitative evaluation, with French healthcare and childcare professionals, of a brochure containing the latest official child feeding recommendations to help prevent childhood obesity

International audienc

Counseling parents about child feeding: a qualitative evaluation of French doctors and health/childcare professionals' experiences and perception of a brochure containing new recommendations

International audienceBackground: Parents are crucial in establishing their children's eating habits, and doctors and health/childcare professionals (HCCPs) can provide meaningful and trusted guidance on feeding, especially in the 0-3-year-old period. With the upcoming release of the official brochure containing the new child feeding recommendations in France, this study aims to: (1) assess professionals' practices and perceptions regarding their communication with parents on child feeding and (2) evaluate their perception of the draft of the new brochure. Methods: A 15-page draft brochure (without pictures) containing updated child feeding recommendations for children 0-3 years old was developed by Sante publique France (the French public health agency). Online semi-structured interviews were conducted with professionals (n = 21), including 13 pediatricians and general practitioners (doctors) and eight healthcare or childcare professionals (HCCPs) two weeks after they were provided with this draft brochure to read. The interview guide was developed and piloted with other professionals (n = 3) prior to these interviews. Interview data were transcribed verbatim and analyzed thematically using an inductive approach. Results: While doctors and HCCPs mostly communicate orally with parents, both acknowledged that the brochure might be a helpful supplement, especially for HCCPs to legitimize their advice to parents. For doctors, giving the brochure to parents may help provide systematic advice and save time during consultations. Professionals serving parents of lower socioeconomic status would prefer a supplement with less text and more illustrations. In general, the messages were perceived to be easily understandable but providing detachable cards to distribute according to the child's age would facilitate information dissemination and might be more useful to parents. Professionals reported that lack of training, the circulation of contradictory information, and language barriers were common challenges. Conclusion: French professionals welcomed the new official brochure as a means to spread updated child feeding recommendations. However, this brochure could be modified and specific tools developed to better adapt to professionals' needs of communication with parents and to facilitate the relay of information. Providing updated and consistent information to parents should be considered a priority for public health stakeholders toward increased adherence to new recommendations

A web-based and mobile intervention with brochure support providing complementary feeding guidelines to first-time parents in France: Randomized Controlled Trial (NutrienT trial)

International audiencePurpose: In light of the latest epidemiological and nutritional knowledge and scientific evidence supporting responsive feeding, the French feeding guidelines for 0-3 years were recently updated and nationally disseminated through a brochure and media campaign by Santé publique France. Moreover, smartphone apps become increasingly popular and is likely relevant to provide timely information across development to inform parents about child feeding practices but their effect is seldom evaluated. This randomized controlled trial (RCT) aims to investigate whether the provision of guidelines through an app and a brochure (vs. brochure alone, usual service) results in healthier parental feeding practices, infant's eating behaviours and body mass index (BMI). Methods: This double-blinded monocentric 2-arm trial is conducted among first-time parents living in the area of Dijon (France) and recruited in a maternity ward. A smartphone app was developed by INRAE for the outcome evaluation and for the timely distribution of the new guidelines content: from child age 3 to 36 months, 106 age-adapted messages with dietary recommendations, educational advice, recipes and tips provided in the form of short texts and videos (intervention group only), and 36 generic messages (both groups). The primary outcome is the BMI z-score at 36 months of age. Secondary outcome measures include online parents' reports and behavioural assessments (experimental meals) of parental feeding practices and infant eating behaviours from inclusion to 36 months of age. Analyses of covariance on these outcomes will assess the effect of the intervention. Mediation and moderation analyses will explore, respectively, the mechanisms of action of the intervention and the potential moderating effect of socioeconomic, parental (attitudes and beliefs about child feeding) and infants' (general temperament) factors. Sample size was determined to be n=118 in each arm, plus 20% to compensate for potential attrition.Results/findings: The first participants were enrolled in March 2022 and the recruitment is ongoing (n=110 were included on February 2023). Conclusions: This is the first French RCT to assess a digital intervention targeted to first-time parents to improve feeding practices and child growth. The app may represent a potential stand-alone communication tool to complement those already disseminated to the general population